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Herein, we describe the catalytic enantioselective cross-coupling of 1,2-bisboronic esters. Prior work on group specific cross coupling is limited to the use of geminal bis-boronates. This desymmetrization provides a novel approach to prepare enantioenriched cyclopropyl boronates with three contiguous stereocenters, that could be further derivatized through selective functionalization of the carbon-boron bond. Our results suggest that transmetallation, which is the enantiodetermining step, takes place with retention of stereochemistry at carbon

The immobilization of TiO2 nanoparticles on graphene acid (GA), a conductive graphene derivative densely functionalized with COOH groups, is presented. The interaction between the carboxyl groups of the surface and the titanium precursor leads to a controlled TiO2 heterogenization on the nanosheet according to microscopic and spectroscopic characterizations. Electronic communication shared among graphene and semiconductor nanoparticles shifts the hybrid material optical features toward less energetic radiation but maintaining the conductivity. Therefore, GA-TiO2 is employed as heterogeneous photocatalyst for the synthesis of 2,5-disubstituted 1,3,4-oxadiazoles using ketoacids and hydrazides as substrates. The material presented enhanced photoactivity compared to bare TiO2, being able to yield a large structural variety of oxadiazoles in reaction times as fast as 1 h with full recyclability and stability. The carbocatalytic character of GA is the responsible for the substrates condensation and the GA-TiO2 light interaction ability is able to photocatalyze the cyclization to the final 1,3,4-oxadiazoles, demonstrating the optimal performance of this multifunctional photocatalytic material, Financial support was provided by the Spanish Government (RTI2018-095038-B-I00), FotoaArt “Comunidad de Madrid”, and European Structural Funds (S2018/NMT-4367) proyectos sinérgicos I+D (Y2020/NMT-6469) and Comunidad Autónoma de Madrid (SI1/PJI/2019-00237). M.B. and M.B. thank the Spanish MICINN for the Juan de la Cierva Incorporación contracts (IJC2019-042157-I and IJC2019- 042430-I). We also acknowledge the electron microscopy analysis from CNME. This work was supported by the national project NovaCO2 (PID2020-118593RB-C22) funded by MCIN/AEI/10.13039/501100011033

In the present work, the energy donor 4,4-difluoro-4-bora-3a,4a-diaza-sindacene (BODIPY) is used for the first time in combination with a pentacene dimer (Pnc2) to provide the conjugate BODIPYPnc2 that features absorption throughout a large part of the solar spectrum. Upon photoexcitation, the singlet excited state energy of BODIPY is transferred to the pentacene dimer via intramolecular Förster resonance energy transfer (FRET). Subsequently, the pentacene dimer undergoes intramolecular singlet fission. In this process, a singlet correlated triplet pair is generated from the first singlet excited state via coupling to an intermediate state. The results show that solvent polarity has an influence on the system, with the largest FRET rate (i.e., 7.46 × 1011 s−1) being obtained in the most polar solvent (namely, benzonitrile) along with the largest triplet quantum yield (i.e., 207 ± 20%), A.-S.W., G.L., and I.P. contributed equally to this work. D.M.G. thanks the financial support from ″the German Research Foundation (DFG) via SFB 953 “Synthetic Carbon Allotropes” and “Solar Technologies go Hybrid (SolTech)” Initiative of the Bavarian Ministry for Science. T.T. acknowledges financial support from MICINN (PID2020-116490GB-I00 and TED2021-131255B-C43), the Comunidad de Madrid and the Spanish State through the Recovery, Transformation and Resilience Plan [“Materiales Disruptivos Bidimensionales (2D)” (MAD2D-CM) (UAM1)-MRR Materiales Avanzados], and the European Union through the Next Generation EU funds. IMDEA Nanociencia acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686). R.R.T. acknowledges funding from the Natural Sciences and Engineering Research Council of Canada (NSERC, grant no. RGPIN-2017-05052) and the Canada Foundation for Innovation (CFI)

Self-sorting phenomena are the basis of manifold relevant (bio)chemical processes where a set of molecules is able to interact with no interference from other sets and are ruled by a number of codes that are programmed in molecular structures. In this work, we study, the relevance of chelate cooperativity as a code for achieving high self-sorting fidelities. In particular, we establish qualitative and quantitative relationships between the cooperativity of a cyclic system and the self-sorting fidelity when combined with other molecules that share identical geometry and/or binding interactions. We demonstrate that only systems displaying sufficiently strong chelate cooperativity can achieve quantitative narcissistic self-sorting fidelities either by dictating the distribution of cyclic species in complex mixtures or by ruling the competition between the intra- and intermolecular versions of a noncovalent interaction., European Research Council (ERC-Starting Grant 279548 PROGRAM-NANO) and MICINN (CTQ2017-84727-P, RED2018-102331-T, and PID2020-116921GB-I00)

The activation of molecules through intramolecular hydrogen-bond formation to promote chemical reactions appears as a suitable strategy in organic synthesis, especially for the preparation of chiral compounds under metal and organocatalytic conditions. The use of this interaction has enabled reactivity enhancement of reagents, as well as stabilization of the chemical species and enantiocontrol of the processes, Financial support was provided by the European Research Council (ERC-CoG, Contract No. 647550, ERC-PoC, Contract No. 861930), the Spanish Government (RTI2018- 095038-B-I00), “Comunidad de Madrid”, and European Structural Funds (S2018/NMT-4367) and proyectos sinérgicos I+D (Y2020/NMT-6469). A.G.-C. acknowledges a predoctoral FPI fellowship

The internal cavity formed by a dimeric subphthalocyanine (SubPc) capsule (SubPc2Pd3, 2), ensembled by coordination of pyridyl substituents in the monomeric SubPc 1 to Pd centers, has proved an optimal space for the complexation of C60 fullerene. Taking advantage of the intense absorption of green light of the SubPc component at around 550 nm, we have tested different green-light induced photoredox addition reactions over the double bonds of guest C60. Both addition of amine radicals, generated by reductive quenching of the excited state of 2 by aromatic trimethylsilylamines, and addition of trifluoroethyl radicals, obtained from oxidative quenching of the photosensitizer, have successfully taken place with good yields in the 2:C60 host:guest complex. On the other hand, both the photoredox reactions result in much lower yields when the monomeric pyridyl-SubPc is used as a photocatalyst, demonstrating that encapsulation results in a strong acceleration of the reaction. Importantly, this is the first example of the use of a confined microenvironment to trigger photoredox chemical transformations of fullerenes

A major challenge for understanding the origins of life is to explore how replication networks can engage in an evolutionary process. Herein, we shed light on this problem by implementing a network constituted by two different types of extremely simple biological components: the amino acid cysteine and the canonical nucleobases adenine and thymine, connected through amide bonds to the cysteine amino group and oxidation of its thiol into three possible disulfides. Supramolecular and kinetic analyses revealed that both self- and mutual interactions between such dinucleobase compounds drive their assembly and replication pathways. Those pathways involving sequence complementarity led to enhanced replication rates, suggesting a potential bias for selection. The interplay of synergistic dynamics and competition between replicators was then simulated, under conditions that are not easily accessible with experiments, in an open reactor parametrized and constrained with the unprecedentedly complete experimental kinetic data obtained for our replicative network. Interestingly, the simulations show bistability, as a selective amplification of different species depending on the initial mixture composition. Overall, this network configuration can favor a collective adaptability to changes in the availability of feedstock molecules, with disulfide exchange reactions serving as 'wires' that connect the different individual auto- and cross-catalytic pathways.

Pt(II)-BODIPY complexes combine the chemotherapeutic activity of Pt(II) with the photocytotoxicity of BODIPYs. Additional conjugation with targeting ligands can boost the uptake by cancer cells that overexpress the corresponding receptors. We describe two Pt(II) triangles, 1 and 2, built with pyridyl BODIPYs functionalized with glucose (3) or triethylene glycol methyl ether (4), respectively. Both 1 and 2 showed higher singlet oxygen quantum yields than 3 and 4, due to the enhanced singlet-to-triplet intersystem crossing. To evaluate the targeting effect of the glycosylated derivative, in vitro experiments were performed using glucose transporter 1 (GLUT1)-positive HT29 and A549 cancer cells, and noncancerous HEK293 cells as control. Both 1 and 2 showed higher cellular uptake than 3 and 4. Specifically, 1 was selective and highly cytotoxic toward HT29 and A549 cells. The synergistic chemo- and photodynamic behavior of the metallacycles was also confirmed. Notably, 1 exhibited superior efficacy toward the cisplatin-resistant R-HepG2 cells, Financial support from Spanish MINECO (PID2020- 116490GB-I00 and PID2020-115801RB-C21) is acknowledged. We also thank financial support to the Comunidad de Madrid (MAD2D-CM) and MICINN (“Planes complementarios, Materiales Avanzados”). IMDEA Nanociencia acknowledges support from the “Severo Ochoa” Program for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686). E.Y.X. thanks The Chinese University of Hong Kong for support through the Impact Postdoctoral Fellowship Scheme

Large π-conjugated systems are key in the area of molecular materials. Herein, we prepare via AuI - catalyzed cyclization a series of fully π-conjugated anthracene-fused oligo-BODIPYs. Their structural and optoelectronic properties were studied by several techniques, ranging from X-ray, UV/Vis, and cyclic voltammetry to transient absorption spectroscopy. As a complement, their electronic structures were explored by means of Density Functional Theory (DFT) calculations. Depending on the size and shape of the π-conjugated skeleton, unique features—such as face-to-face supramolecular organization, NIR absorption and fluorescence as well as strong electron accepting character—were noted. All in all, the aforementioned features render them valuable for technological applications, ments We gratefully acknowledge financial support from the Spanish MICINN through Projects PID2020-116490GB-I00 (Porphyrinoids) and TED2021-131255B-C43 (PERSOLAR). We also thank financial support to the Comunidad de Madrid (MAD2D-CM) and MICINN through project “Materiales disruptivos bidimensionales (2D)” within the Plan de recuperación, transformación y resiliencia (Materiales avanzados). IMDEA Nanociencia acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686). J.L. acknowledges MECD, Spain, for a F.P.U. fellowship. European Commission under the Marie Sklodowska-Curie Action Cofund 2015 (EU project 713366-InterTalentum) is acknowledged for the support for G.D.S. Generous allocation of computational time from the Centro de Computación Científica UAM is gratefully acknowledged. Work in Erlangen was supported by the Deutsche Forschungsgemeinschaft (DFG) through SFB 953 project B10 and the Bavarian Collaborative Research Project “Solar Technologies go Hybrid” (SolTech)

Porphyrinoids are considered perfect candidates for the preparation of model electron donor-acceptor (D-A) systems as they enable fast and efficient photoinduced electron transfer. Herein, we report on the synthesis and photophysical characterization of a ZnPc SubPc conjugate covalently connected through a short-range alkyne spacer. We designed and prepared the conjugate, which comprise, on the one hand, a perfluorinated SubPc with strong electron acceptor character and, on the other, a Pc peripherally functionalized with carbazoles with strong electron donor character. Photoinduced electron transfer events are in-depth analyzed by several techniques, including steady-state absorption, time-resolved emission and transient absorption measurements on different time scales. Our studies confirm a full charge separation occurring from a photoexcited charge transfer state, 68. Acknowledgements Financial support from Spanish MINECO (PID2020-116490GB I00, Porphyrinoids) is acknowledged. IMDEA Nanociencia acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686). J.L. acknowledges MECD, Spain, for a F.P.U. fellowship. Kuwait Foundation for the Advancement of Science (KFAS) and the RSP unit general facilities of the Faculty of Science GFS (GS 01/01, GS 02/01, GS 03/01, GS 01/03, GS 01/05) is acknowledged. Work in Erlangen was supported by the Deutsche Forschungsgemeinschaft (DFG) through SFB 953 project B10 and the Bavarian Collaborative Research Project “Solar Technologies go Hybrid" (SolTech)

The selective δ-C(sp3)−H acetoxylation of N-(SO2Py)-protected amino acid derivatives has been accomplished by using palladium-catalysis and PhI(OAc)2 (PIDA) as both terminal oxidant and acetoxy source. The distinct structural and electronic features of the SO2Py compared to more traditional carbonyl-based directing groups is essential to override the otherwise more favourable competitive intramolecular C−H amination. The δ-site selectivity predominates over traditionally more favorable 5-membered cyclopalladation at competitive γ-CH2. Experimental and DFT mechanistic studies provide important insights about the mechanism and the underlying factors controlling the chemo- and regioselectivity, We thank the Ministerio de Ciencia e Innovación (MICINN) and Fondo Europeo de Desarrollo Regional (FEDER, UE) for financial support (Agencia Estatal de Investigación/Project PGC2018-098660-B-I00). M.M.-M. thanks MINECO for a FPI predoctoral fellowship and D.S.P. thanks Fonds der chemischen Industrie FCI (PhD fellowship) for financial support

We have developed a Ni-catalyzed cascade cyclization/Negishicoupling reaction for the formation of pyrrolidines and pyrrolidinones starting from N-protected allylamines and acrylamides which contain a redox active ester group. The reaction provides two C C bonds in a single operation and takes place with both alkylzinc and arylzinc bromides as nucleophiles. Activation of RAE by low valent Ni complexes involving a radical pathway followed by a fast cyclization of intermediate carbon radicals is propose, We thank the support by MICIU(CTQ2016-79826-R and PID2019- 109088GB I00) and for a FPI fellowship to J. C. N.

A highly efficient enantioselective inverse-electron-demand aza-Diels-Alder reaction between aza-sulfonyl-1-aza-1,3-butadienes and silyl (di)enol ethers has been developed. The presented methodology allows the synthesis of benzofuran-fused 2-piperidinol derivatives with three contiguous stereocenters in a highly selective manner, as even the hemiaminal center is completely stereocontrolled. Density functional theory (DFT) calculations support that the hydrogen-bond donor-based bifunctional organocatalyst selectively triggers the reaction through the ipso,α-position of the dienophile, in contrast to the reactivity observed for dienolates in situ generated from β,γ-unsaturated derivatives. Moreover, the calculations have clarified the mechanism of the reaction and the ability of the hydrogen-bond donor core to hydrolyze selectively theEisomer of the dienol ether. Furthermore, to demonstrate the applicability of silyl enol ethers as nucleophiles in the asymmetric synthesis of interesting benzofuran-fused derivatives, the catalytic system has also been implemented for the highly efficient installation of an aromatic ring in the piperidine adducts, Financial support was provided by the European Research Council (ERC-CoG, contract number: 647550), Spanish Government (RTI2018-095038-B-I00), and “Comunidad de Madrid” and European Structural Funds (S2018/NMT-4367)

We present a strategy for the synthesis of spirocyclic cyclobutanes with modulable exit vectors based on the regioselective monoborylation of spirocyclobutenes. Using an inexpensive copper salt and a commercially available bidentate phosphine, a broad variety of borylated spirocycles have been prepared with complete regiocontrol. The boryl moiety provides a synthetic handled for further functionalization, allowing access to a wide array of spirocyclic building blocks from a common intermediate, We thank the European Research Council (ERC-337776) and MINECO and MICIIN (CTQ2016-78779-R and PID2019-107380GB-I00 to M.T.; PID2019106184GB-I00 and RED2018-102387-T to I.F.) for financial support. L.N. thanks Comunidad de Madrid for a predoctoral fellowship. We acknowledge Dr. Josefina Perles (UAM) for X-ray structure análisis

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Orgánica. Fecha de Lectura: 22-09-2022, This thesis has been focused on the functionalization of nanostructures for their use in drug delivery projects or the development of sensors of nucleic acids. In this regard, several linkers for the functionalization of nanostructures have been prepared, which have been designed to contain different reactive moieties, such as dithiolane or maleimide. Moreover, these derivatives have been prepared with stimuli-responsive bonds to ease the release of the drugs or oligonucleotides. Also, a new protocol to quantify the loading of oligonucleotides on gold nanoparticles was developed. In this case, after some manipulations of the samples, the oligonucleotides were quantified from the supernatant by absorbance spectrum using a corresponding calibration curve. In this line, the procedure to modify AuNPs has been optimized, achieving excellent results in a very short time (1 hour). With modified AuNPs, some applications have been developed, such as a novel catalytic complex and ligand for CuAAC fluorogenic reactions. Using the catalytic complex approach the best results were obtained with a PolyG of 12 nts. On the other hand, using the nanoparticles as ligand, the best results were obtained with the PolyT of 12 nts. Also, nanostructures as gold and albumin-based nanoparticles have been functionalized with different drugs (SN38, AZD8055 or Doxorubicin) and used for the treatment of cancer with excellent results. Modified gold nanoparticles have also been used as biosensors of nucleic acids involved in diseases, such as cancer or SARS-CoV-2. For the detection of cancer, a nanostructure containing a molecular beacon-like oligonucleotide with several modifications has been used to develop a sensor for Uveal melanoma. In this case, a double stimuli system has been implemented to control better the specificity and intensity of the system. For SARS-CoV-2 detection, two approaches have been developed. One approach is based on a molecular beacon-like structure containing a cholesterol modification, which in the presence of the target sequence, the nanoparticles aggregate. The other approach exploits a CRISPR/CAS-based Colorimetric nucleic Acid Detection (CASCADE) system that, in the presence of the target sequence, Cas13 nuclease activity was activated, leading to the aggregation of the nanoparticles

Selective functionalization of the C-B bond in 1,2-bis(boronate) esters has emerged as a powerful tool to prepare 1,2-difunctionalized compounds with stereocontrol. Selective Suzuki cross-coupling, oxidation, amination, and homologation reactions serve as platforms to prepare a wide variety of compounds from a common intermediate. The exquisite selectivity offered and their easy preparation from feedstock material using a myriad of catalytic transformations make them attractive building blocks for the preparation of complex molecules. In this Perspective, we summarize the examples of selective C-B bond functionalization of vicinal bis(boronates), attending to the nature of the C-B bond functionalization., This work was supported by the MICINN (PID2019-107380GB-I00)

The exceptional versatility of sulfones has been extensively exploited in organic synthesis across several decades. Since the first demonstration in 2005 that sulfones can participate in Pd-catalysed Suzuki-Miyaura type reactions, tremendous advances in catalytic desulfitative functionalizations have opened a new area of research with burgeoning activity in recent years. This emerging field is displaying sulfone derivatives as a new class of substrates enabling catalytic C-C and C-X bond construction. In this review, we will discuss new facets of sulfone reactivity toward further expanding the flexibility of C-S bonds, with an emphasis on key mechanistic features. The inherent challenges confronting the development of these strategies will be presented, along with the potential application of this chemistry for the synthesis of natural products. Taken together, this knowledge should stimulate impactful improvements on the use of sulfones in catalytic desulfitative C-C and C-X bond formation. A main goal of this article is to bring this technology to the mainstream catalysis practice and to serve as inspiration for new perspectives in catalytic transformations.

Magnetism is typically associated with d- or f-block elements, but can also appear in organic molecules with unpaired π-electrons. This has considerably boosted the interest in such organic materials with large potential for spintronics and quantum applications. While several materials showing either d/f or π-electron magnetism have been synthesized, the combination of both features within the same structure has only scarcely been reported. Open-shell porphyrins (Pors) incorporating d-block transition metal ions represent an ideal platform for the realization of such architectures. Herein, the preparation of a series of open-shell, π-extended Pors that contain magnetically active metal ions (i.e., CuII , CoII , and FeII ) through a combination of in-solution and on-surface synthesis is reported. A detailed study of the magnetic interplay between π- and d-electrons in these metalloPors has been performed by scanning probe methods and density functional theory calculations. For the Cu and FePors, ferromagnetically coupled π-electrons are determined to be delocalized over the Por edges. For the CoPor, the authors find a Kondo resonance resulting from the singly occupied CoII dz 2 orbital to dominate the magnetic fingerprint. The Fe derivative exhibits the highest magnetization of 3.67 μB (S≈2) and an exchange coupling of 16 meV between the π-electrons and the Fe d-states.

When aiming to synthesize molecules with elevated molecular complexity starting from relatively simple starting materials, photochemical transformations represent an open avenue to circumvent analogous multistep procedures. Specifically, light‐mediated cycloadditions remain as powerful tools to generate new bonds begotten from non‐very intuitive disconnections, that alternative thermal protocols would not offer. In response to the current trend in both industrial and academic research pointing towards green and sustainable processes, several strategies that meet these requirements are currently available in the literature. This Minireview summarizes [2+2] and [4+2] photocycloadditions that do not require the use of metal photocatalysts by means of alternative strategies. It is segmented according to the cycloaddition type in order to give the reader a friendly approach and we primarily focus on the most recent developments in the field carried out using visible light, a general overview of the mechanism in each case is offered as well., This Minireview seeks to highlight modern advances in the understanding of novel methodologies that open access to visible‐light‐mediated/metal free [2+2] and [4+2] cycloadditions. A collection of examples that displays reactivity and fundamental contributions in this fast‐evolving field of metal‐based photocatalysis; and could be used as a tool for the readers, to adopt as a kaleidoscopic perspective on cycloadditions.

In the endeavor of extending the clinical use of photodynamic therapy (PDT) for the treatment of superficial cancers and other neoplastic diseases, deeper knowledge and control of the subcellular processes that determine the response of photosensitizers (PS) are needed. Recent strategies in this direction involve the use of activatable and nanostructured PS. Here, both capacities have been tuned in two dendritic zinc(II) phthalocyanine (ZnPc) derivatives, either asymmetrically or symmetrically substituted with 3 and 12 copies of the carbohydrate sialic acid (SA), respectively. Interestingly, the amphiphilic ZnPc‐SA biohybrid (1) self‐assembles into well‐defined nanoaggregates in aqueous solution, facilitating cellular internalization and transport whereas the PS remains inactive. Within the cells, these nanostructured hybrids localize in the lysosomes, as usually happens for anionic and hydrophilic aggregated PS. Yet, in contrast to most of them (e. g., compound 2), hybrid 1 recovers the capacity for photoinduced ROS generation within the target organelles due to its amphiphilic character; this allows disruption of aggregation when the compound is inserted into the lysosomal membrane, with the concomitant highly efficient PDT response., An insightful approach towards activatable and nanostructured photosensitizers has been developed by preparing dendritic biohybrids composed of a core phthalocyanine decorated with multiple sialic acid moieties. The resulting hybrids self‐assemble into well‐defined nanoaggregates in aqueous solution, and disaggregate upon reaching the target organelles, resulting in the on‐site activation of a highly efficient photodynamic response.

The great potential of subphthalocyanines (SubPcs) to stabilize boron peroxides has been demonstrated. In particular, a subphthalocyanato boron (III) peroxide has been prepared in good yield via boron triflate. This derivative is remarkably stable under ambient conditions and can be fully characterized. The impact of the peroxide group on the structural and optoelectronic properties of SubPc was examined by NMR and UV/Vis spectroscopies, as well as single-crystal X-ray diffraction analysis. Moreover, density functional theory calculations were performed to explain the experimental results. The reactivity of this peculiar boron peroxide as an oxidant and a Lewis base was also studied.

Herein, a computational predictive tool for redox flow batteries based on NBO and ADCH charge distribution studies is presented and supported by experimental evidence. Using highly water soluble (>2 M) non-planar 2,2′ - bipyridinium salts as a case of study, this work presents a DFT protocol that successfully predicts the stability and forecasts their potential application as active materials for Aqueous Organic Redox Flow Batteries (AORFB). An initial theoretical-experimental characterization of selected bipyridines served to determine the effect of the ring size, geometry, and electron density on the physico-chemical properties of the materials. Nonetheless, the NBO and ADCH charge analyses were essential tools to understand the stability of the reduced species in terms of electronic delocalization and the importance of the molecular design on the stability of electrolyte for AORFB. Based on these results, the cell performance of seven-membered 2,2′ -bypiridinium salt, (2), and m-Me substituted homologous, (4), were compared. The significantly lower capacity decay rendered by compound 4 based electrolyte, (0.35%/cycle) compared with compound 2 based electrolyte, (0.71%/cycle) was in good agreement with the predicted stability. The aim of this work is to highlight the powerful synergy between DFT calculations and organic chemistry in predicting the behaviour of different negolytes, This work has been funded by the European Union under the HIGREEW project, Affordable High-performance Green Redox Flow batteries (Grant agreement no. 875613). H2020: LC-BAT-4-2019. A.C. Lopes acknowledges the Ramon y Cajal (RYC2021-032277-I) research fellowship, the financial support from Ministerio de Ciencia e Innovacion ´ / AEI /10.13039/501100011033 and from European Union NextGenerationEU/PRTR. We also thank the CCC-UAM (Graforr project) for allocation of computer time

Photodynamic therapy is a treatment modality of cancer based on the production of cytotoxic species upon the light activation of photosensitizers. Zinc phthalocyanine photosensitizers bearing four or eight bulky 2,6-di(pyridin-3-yl)phenoxy substituents were synthesized, and pyridyl moieties were methylated. The quaternized derivatives did not aggregate at all in water and retained their good photophysical properties. High photodynamic activity of these phthalocyanines was demonstrated on HeLa, MCF-7, and EA.hy926 cells with a very low EC50 of 50 nM (for the MCF-7 cell line) upon light activation while maintaining low toxicity in the dark (TC50 ≈ 600 μM), giving thus good phototherapeutic indexes (TC50/EC50) above 1400. The compounds localized primarily in the lysosomes, leading to their rupture after light activation. This induced an apoptotic cell death pathway with secondary necrosis because of extensive and swift damage to the cells. This work demonstrates the importance of a bulky and rigid arrangement of peripheral substituents in the development of photosensitizers, The work was supported by the Czech Science Foundation (19-14758Y), Charles University (PRIMUS/20/SCI/013, GAUK 1620219, SVV 260 550), and by the project EFSACDN (No. CZ.02.1.01/0.0/0.0/16_019/0000841) cofunded by the ERDF. For affiliations ‡, ∥, and ⊥, the work was supported by MINECO-Feder funds (CTQ2017-85393-P (T.T.), CTQ-2014-53673-P and CTQ-2017-89539-P (A.d.l.E.), PCIN-2017-042/EuroNanoMed2017-191, TEMPEAT (T.T.)). Affiliation ⊥ (IMDEA Nanociencia) also acknowledges support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686)

This is the peer reviewed version of the following article: Angewandte Chemie - International Edition 60.9 (2021): 4555-4560, which has been published in final form at https://doi.org/10.1002/anie.202013020. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited, Herein, a light-driven, atom-economical process that provides access to enantiomerically enriched substituted chiral 1-pyrroline derivatives is introduced. The strategy involves the distal functionalization of acyl heterocycles through a hydrogen-atom transfer (HAT) process and the use of tailor-made ketimines as reliable electrophilic partners. This transformation is translated into an enantiomerically controlled radical/polar cascade reaction in which water is produced as the sole by-product and stereoselectivity is dictated by coordination to a chiral-at-rhodium catalyst, Financial support was provided by the European Research Council (ERC-CoG, contract number: 647550, 861930), Spanish Government (RTI2018-095038-B-I00), “Comunidadde Madrid” and European Structural Funds (S2018/NMT-4367)

The design and production of the next generations of synthetic aqueous self-Assembled systems able to mimic some biological features will require increasingly sophisticated monomer constituents that make use of additional interactions to hydrophibic effects to attain enhanced structural and functional complexity. Here, we broadly investigate the aqueous self-Assembly of dinucleobase amphiphilic monomers into helical nanotubes under a wide range of different conditions of temperature, concentration, solvent composition and pH. Such monomers comprise an amphiphilic π-conjugated central block, endowed with a lipophilic chiral tail and a hydrophilic group that can be made anionic (carboxylate), neutral (glycol) or cationic (ammonium), disubstituted with complementary guanine and cytosine nucleobases at each termini. These molecules self-Assemble into amphiphilic nanotubes in water but, when subjected to diverse (drastic) changes in the experimental conditions, undergo either disassembly into monomers, chiral reorganization, or a morphological restructuration into globular objects due to dehydration of the peripheral hydrophilic groups, Funding from the European Research Council (ERC-Starting Grant 279548 PROGRAM-NANO) and MINECO (CTQ2017- 84727-P) is gratefully acknowledged. F. A. is grateful to MSCA-COFUND InterTalentum (713366) and MSCA-IF (793506) programs. P. C. acknowledges the Comunidad de Madrid for the PEJ-2017-AI/IND-6246 contract

The modification of surfaces with multiple ligands allows the formation of platforms for the study of multivalency in diverse processes. Herein we use this approach for the implementation of a photosensitizer (PS)-nanocarrier system that binds efficiently to siglec-10, a member of the CD33 family of siglecs (sialic acid (SA)-binding immunoglobulin-like lectins). In particular, a zinc phthalocyanine derivative bearing three SA moieties (PcSA) has been incorporated in the membrane of small unilamellar vesicles (SUVs), retaining its photophysical properties upon insertion into the SUV's membrane. The interaction of these biohybrid systems with human siglec-10-displaying supported lipid bilayers (SLBs) has shown the occurrence of weakly multivalent, superselective interactions between vesicle and SLB. The SLB therefore acts as an excellent cell membrane mimic, while the binding with PS-loaded SUVs shows the potential for targeting siglec-expressing cells with photosensitizing nanocarriers, This work was supported by MINECO-Feder funds [PID2020-116490GB-I00, Porphyrinoids (T.T.) and PID2020-119306GB-100 (AdlE)]. IMDEA Nanociencia also acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant SEV2016-0686). S.L. and M.C.B. acknowledge financial support by The Netherlands Organization for Scientific Research (NWO, TOP grant 715.015.001 to J.H.)

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Química Orgánica. Fecha de Lectura: 13-06-2022, La financiación de este trabajo ha provenido del Consejo Europeo de I nvestigación (ERC-CG, número de contrato 647550), del Ministerio de Economía y C ompetitividad (CTQ-2015-64561-R y RTI2018-095038- B-I00), de la “Comunidad de Madrid” y d e los Fondos Estructurales y de Inversión Europeos (S2018/NMT-4367)

The cooperative action of the acetate ligand, the 2- pyridyl sulfonyl (SO2Py) directing group on the alkyne substrate, and the palladium catalyst has been shown to be crucial for controlling reactivity, regioselectivity, and stereoselectivity in the acetoxylation of unsymmetrical internal alkynes under mild reaction conditions. The corresponding alkenyl acetates were obtained in good yields with complete levels of β-regioselectivity and anti-acetoxypalladation stereocontrol. Experimental and computational analyses provide insight into the reasons behind this delicate interplay between the ligand, directing group, and the metal in the reaction mechanism. In fact, these studies unveil the multiple important roles of the acetate ligand in the coordination sphere at the Pd center: (i) it brings the acetic acid reagent into close proximity to the metal to allow the simultaneous activation of the alkyne and the acetic acid, (ii) it serves as an inner-sphere base while enhancing the nucleophilicity of the acid, and (iii) it acts as an intramolecular acid to facilitate protodemetalation and regeneration of the catalyst. Further insight into the origin of the observed regiocontrol is provided by the mapping of potential energy profiles and distortion−interaction analysis, We thank the Ministerio de Ciencia e Innovación (MICINN) and Fondo Europeo de Desarrollo Regional (FEDER, UE) for financial support (Agencia Estatal de Investigación/Projects PGC2018-098660-B-I00 and PGC2018-094644-B-C21). J.C. and I.C. thank MECD and MINECO for an FPU fellowship and a Ramón y Cajal contract, respectively. We also acknowledge the Centro de Computación Científica of the Universidad Autónoma de Madrid for computational time. We thank Inés Manjón for generous donation of precursors for the synthesis of starting materials. We also thank the referees for their careful and insightful feedback, which helped us to improve our manuscript and to gain a better understanding of the reaction

Herein, we report, a general, facile and environmentally friendly Minisci-type alkylation of N-heteroarenes under simple and straightforward electrochemical conditions using widely available alkyl halides as radical precursors. Primary, secondary and tertiary alkyl radicals have been shown to be efficiently generated and coupled with a large variety of N-heteroarenes. The method presents a very high functional group tolerance, including various heterocyclic-based natural products, which highlights the robustness of the methodology. This applicability has been further proved in the synthesis of various interesting biologically valuable building blocks. In addition, we have proposed a mechanism based on different proofs and pieces of electrochemical evidence

We present the synthesis, photophysical properties, and biological application of nontoxic 3-azo-conjugated BODIPY dyes as masked fluorescent biosensors of hypoxia-like conditions. The synthetic methodology is based on an operationally simple N=N bond-forming protocol, followed by a Suzuki coupling, that allows for a direct access to simple and underexplored 3-azo-substituted BODIPY. These dyes can turn on their emission properties under both chemical and biological reductive conditions, including bacterial and human azoreductases, which trigger the azo bond cleavage, leading to fluorescent 3-amino-BODIPY. We have also developed a practical enzymatic protocol, using an immobilized bacterial azoreductase that allows for the evaluation of these azo-based probes and can be used as a model for the less accessible and expensive human reductase NQO1. Quantum mechanical calculations uncover the restructuration of the topography of the S1 potential energy surface following the reduction of the azo moiety and rationalize the fluorescent quenching event through the mapping of an unprecedented pathway. Fluorescent microscopy experiments show that these azos can be used to visualize hypoxia-like conditions within living cells, This article is dedicated to Professor M. Carmen Carreño on the occasion of her retirement. We thank MINECO (grant CTQ2017-85454-C2-2-P), MICINN (grant PID2020- 113059GB-C22), MCIU (grant PGC2018-094644-B-C21), the Ramón y Cajal Program (grant RYC-2016-20489), the Fundación La Caixa (grant no. LCF/BQ/DR19/11740024), and the Comunidad Autónoma de Madrid (B2017/BMD-3867 RENIMCM) and co-financed by the European Structural and investment fund for financial support. I.C. and F.R.-G. also acknowledge the Red Española de Supercomputación, the MareNostrum Supercomputer Center, and the Centro de Computación Científica of the UAM (CCC-UAM) for the generous allocation of computer time and for their technical support. We thank the “Servicio de Microscopía óptica y confocal CBMSO” facility for their assistance. We also thank Prof. M. C. Carreño for her advice and helpful discussions during the work

Misfolding of secretory proteins in the endoplasmic reticulum (ER) features in many human diseases. In α1-antitrypsin deficiency, the pathogenic Z variant aberrantly assembles into polymers in the hepatocyte ER, leading to cirrhosis. We show that α1-antitrypsin polymers undergo a liquid:solid phase transition, forming a protein matrix that retards mobility of ER proteins by size-dependent molecular filtration. The Z-α1-antitrypsin phase transition is promoted during ER stress by an ATF6-mediated unfolded protein response. Furthermore, the ER chaperone calreticulin promotes Z-α1-antitrypsin solidification and increases protein matrix stiffness. Single-particle tracking reveals that solidification initiates in cells with normal ER morphology, previously assumed to represent a healthy pool. We show that Z-α1-antitrypsin-induced hypersensitivity to ER stress can be explained by immobilization of ER chaperones within the polymer matrix. This previously unidentified mechanism of ER dysfunction provides a template for understanding a diverse group of related proteinopathies and identifies ER chaperones as potential therapeutic targets., Alpha-1 Foundation Grifols Alpha-1-Antitrypsin Laurell’s Training Award National Biofilms Innovation Centre MINECO MedImmune Infinitus NIH The American Cancer Society The Pershing Square Sohn Cancer Research Award The Chan Zuckerberg Initiative UK Dementia Research Institute grant Canadian Institutes of Health Research US Alzheimer Society Integrated Biological Imaging Network

Glass-forming ability is one of the most desired properties of organic compounds dedicated to optoelectronic applications. Therefore, finding general structure–property relationships and other rules governing vitrification and related near-glass-transition phenomena is a burning issue for numerous compound families, such as Schiff bases. Hence, we employ differential scanning calorimetry, broadband dielectric spectroscopy, X-ray diffraction and quantum density functional theory calculations to investigate near-glass-transition phenomena, as well as ambient- and high-pressure molecular dynamics for two structurally related Schiff bases belonging to the family of glycine imino esters. Firstly, the surprising great stability of the supercooled liquid phase is shown for these compounds, also under high-pressure conditions. Secondly, atypical self-organization via bifurcated hydrogen bonds into lasting centrosymmetric dimers is proven. Finally, by comparing the obtained results with the previous report, some general rules that govern ambient- and high-pressure molecular dynamics and near-glass transition phenomena are derived for the family of glycine imino esters. Particularly, we derive a mathematical formula to predict and tune their glass transition temperature (Tg) and its pressure coefficient (dTg/dp). We also show that, surprisingly, despite the presence of intra- and intermolecular hydrogen bonds, van der Waals and dipole–dipole interactions are the main forces governing molecular dynamics and dielectric properties of glycine imino esters.

Herein, we report the enantioselective addition of remote alkyl radicals, generated from the ring opening of unstrained cycloalkanols by a proton-coupled electron transfer (PCET) process, to 2-acyl imidazoles previously coordinated to a rhodium-based chiral Lewis acid. High yields and enantioselectivites up to 99% are achieved in 1 h. Mechanistic investigations support the formation of the remote alkyl radical by a PCET process, and theoretical studies explain the observed stereochemistry in the addition step, Financial support was provided by the Spanish Government (RTI2018-095038-B-I00, PID2019-110091GB-I00″), “Comunidad de Madrid” and European Structural Funds (S2018/ NMT-4367) and proyectos sinérgicos I+D (Y2020/NMT6469) and Comunidad Autónoma de Madrid (SI1/PJI/2019- 00237). N.S. thanks MINECO for an FPU predoctoral fellowship, and L.M. thanks CAM for an “Atracción de Talento Investigador” contract (2017-T2/AMB-5037). We acknowledge the generous allocation of computer time at the Centro de Computación Científica at the Universidad Autónoma de Madrid (CCC-UAM)

Due its complementary absorptions in the range of 450 and 600 nm, an energy‐donating hexaaryl‐subporphyrazine has been linked to a pentacene dimer, which acts primarily as an energy acceptor and secondarily as a singlet fission enabler. In the corresponding conjugate, efficient intramolecular Förster resonance energy transfer (i‐FRET) is the modus operandi to transfer energy from the subporphyrazine to the pentacene dimer. Upon energy transfer, the pentacene dimer undergoes intramolecular singlet fission (i‐SF), that is, converting the singlet excited state, via an intermediate state, into a pair of correlated triplet excited states. Solvatochromic fluorescence of the subporphyrazine is a key feature of this system and features a red‐shift as large as 20 nm in polar media. Solvent is thus used to modulate spectral overlap between the fluorescence of subporphyrazine and absorption of the pentacene dimer, which controls the Förster rate constant, on one hand, and the triplet quantum yield, on the other hand. The optimum spectral overlap is realized in xylene, leading to Förster rate constant of 3.52×1011 s−1 and a triplet quantum yield of 171 % ±10 %. In short, the solvent polarity dependence, which is a unique feature of subporphyrazines, is decisive in terms of adjusting spectral overlap, ensuring a sizable Förster rate constant, and maximizing triplet quantum yields. Uniquely, this optimization can be achieved without a need for synthetic modification of the subporphyrazine donor., The solvatochromic fluorescence properties of a subporphyrazine are used to control the rate of intramolecular Förster resonance energy transfer (i‐FRET) in a subporphyrazine–pentacene conjugate (SubPzPnc2) that undergoes intramolecular singlet fission (i‐SF). A simple selection of solvent serves to optimize the triplet quantum yield by enhancing the spectral overlap between the fluorescence of the SubPz and the absorption of the Pnc dimer.

A well-established strategy to synthesize heterogeneous, metal-organic framework (MOF) catalysts that exhibit nanoconfinement effects, and specific pores with highly-localized catalytic sites, is to use organic linkers containing organocatalytic centers. Here, we report that by combining this linker approach with reticular chemistry, and exploiting three-dimensioanl (3D) MOF-structural data from the Cambridge Structural Database, we have designed four heterogeneous MOF-based catalysts for standard organic transformations. These programmable MOFs are isoreticular versions of pcu IRMOF-16, fcu UiO-68 and pillared-pcu SNU-8X, the three most common topologies of MOFs built from the organic linker p,p’-terphenyldicarboxylic acid (tpdc). To synthesize the four squaramide-based MOFs, we designed and synthesized a linker, 4,4’-((3,4‐dioxocyclobut‐1‐ene‐1,2‐diyl)bis(azanedyil))dibenzoic acid (Sq_tpdc), which is identical in directionality and length to tpdc but which contains organocatalytic squaramide centers. Squaramides were chosen because their immobilization into a framework enhances its reactivity and stability while avoiding any self-quenching phenomena. Therefore, the four MOFs share the same organocatalytic squaramide moiety, but confine it within distinct pore environments. We then evaluated these MOFs as heterogeneous H-bonding catalysts in organic transformations: a Friedel-Crafts alkylation and an epoxide ring-opening. Some of them exhibited good performance in both reactions but all showed distinct catalytic profiles that reflect their structural differences., This work was supported by the Spanish MINECO (projects RTI2018-095622-B-I00 and RTI2018-095038-B-I00), the Catalan AGAUR (project 2017 SGR 238), the ERC under the EU FP7 (ERC−Co 615954), European Union’s Horizon 2020 research and innovation program under grant agreement No. 685727, and European Structural Funds (S2018/NMT-4367). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706).

The assembly of 3-dimensional covalent organic frameworks on the surface of carbon nanotubes is designed and successfully developed for the first time via the hybridization of imine-based covalent organic frameworks (COF-300) and oxidized MWCNTs by one-pot chemical synthesis. The resulting hybrid material ox-MWCNTs@COF exhibits a conformal structure that consists of a uniform amorphous COF layer covering the ox-MWCNT surface. The measurements of individual hybrid nanotube mechanical strength performed with atomic force microscopy provide insights into their stability and resistance. The results evidence a very robust hybrid tubular nanostructure that preserves the benefits obtained from COF, such as CO2 adsorption. Further digestion of the organic structure with aniline enables the study of the interplay between the hybrid interface and its nanomechanics. This new hybrid nanomaterial presents exceptional mechanical and electrical properties, merging the properties of the CNT template and COF-300., We thank the Spanish Government (RTI2018-095038-B-I00), “Comunidad de Madrid” and European Structural Funds (S2018/NMT-4367). P. J. P. thanks to “María de Maeztu” Program for Units of Excellence in R&D (MDM-2014-0377), FIS2017-89549-R and Human Frontiers Science Program (HFSPO RGP0012/2018). C. S. M. acknowledges support from the Spanish State Research Agency and European Regional Development Fund [BFU2016-74868-P]. M. H.-P. is a recipient of a Juan de la Cierva postdoctoral contract funded by the Spanish Ministry of Economy and Competitivity. M. P.-I. holds a predoctoral fellowship funded by La Caixa Foundation.

Substituted 1,3-diazabicyclo[3.1.0]hexanes with two contiguous quaternary stereocentres are readily prepared by catalytic asymmetric [3+2] cycloaddition of α-substituted iminoesters with azirines. High diastereoselectivities and enantioselectivities (up to 98% ee) are achieved using CuI/(R)-Fesulphos as the catalytic system, We thank the Spanish Ministerio de Economía, Industria y Competitividad (Grant CTQ2015-66954-P, MINECO/FEDER, UE) and FEDER/Ministerio de Ciencia, Innovación y Universidades – Agencia Estatal de Investigación (Grant PGC2018-098660-B-I00) for financial support

The application of proton coupled electron transfer (PCET) processes in organic synthesis has opened the door to new radical intermediates for synthesis such as alkyl radicals in remote positions to a ketone. Herein, we present the addition of these remote alkyl radicals to electron deficient double bonds under photoorganocatalyzed and very mild conditions. The method is not only applicable to diactivated double bonds, but monoactivated ones are also accessible using more stabilized alkyl radicals, and alkyl chains of any length can be introduced. The final products can be easily converted into more complex structures via a one-pot process, and the activating functional groups were transformed in the more versatile methyl esters. Mechanistic investigations support a mechanistic proposal based on a PCET process. (Figure presented.), Financial support was provided by the Spanish Government (RTI2018-095038 B I00, PID2019-110091GB I00), “Comunidad de Madrid”, and European Structural Funds (S28/ NMT-4367) and proyectos sinérgicos I+D (Y2020/NMT-6469) and Comunidad Autónoma de Madrid (PEJD-2019-PRE/AMB16640 and SI1/PJI/2019-00237). N. S. thanks MINECO for a FPU predoctoral fellowship and L. M thanks CAM for an “Atracción de Talento Investigador” contract (2017-T2/AMB5

The stereoselective photoisomerization of olefins via Energy Transfer (EnT) sensitization bears significant potential in the context of rational design of catalytic stereodivergent methodologies. Whereas approaches for controlling the access to E- and Z- isomers depend highly on the nature of the catalyst – and therefore are not easily implemented as a general strategy – EnT catalysis has emerged in recent years as an increasingly powerful tool for olefin geometry control in a nearly perfect step-economic fashion. Moreover, this approach presents both high functional group tolerance and, most notably, has demonstrated ample multicatalytic compatibility. This feature has enabled the development of tandem stereodivergent catalytic strategies, which are the focus of this Review. (Figure presented.), We thank the Ministerio de Ciencia e Innovación (MICINN) and Fondo Europeo de Desarrollo Regional (FEDER, UE) for financial support (Agencia Estatal de Investigación/project PGC2018-098660-B-I00). J. C. thanks the Ministerio de Educación, Cultura y Deportes for a FPU fellowship. We thank Inés Manjón for helpful suggestions. We thank Maria T. Quirós for the design and creation of the TOC graphic of this review. We also thank the referees of this review for their comments, which helped improve the quality of the manuscript

A three-step synthetic route giving access to nonsymmetrical bisazolyl 2,4,6-trisubstituted pyridines with different substituents on the pyrazole, indazole, and pyridine heterocycles is described. From the readily available 4-bromo-2,6-difluoropyridine, both fluorine atoms allow for easy selective stepwise substitution, and the bromine atom provides easy access to additional functionalities through both Suzuki and Sonogashira Pd(0) cross-coupling reactions. These synthons represent optimal structures as building blocks in complexation and metalloorganic structures for the tuning of their chelating and photophysical properties.

Rhamnolipids are becoming an important class of glycolipid biosurfactants. Herein, we describe for the first time the enzymatic synthesis of rhamnose fatty acid esters by the transesterification of rhamnose with fatty acid vinyl esters, using lipase from Pseudomonas stutzeri as a biocatalyst. The use of this lipase allows excellent catalytic activity in the synthesis of 4-O-acylrhamnose (99% conversion and full regioselectivity) after 3 h of reaction using tetrahydrofuran (THF) as the reaction media and an excess of vinyl laurate as the acyl donor. The role of reaction conditions, such as temperature, the substrates molar ratio, organic reaction medium and acyl donor chain-length, was studied. Optimum conditions were found using 35 °C, a molar ratio of 1:3 (rhamnose:acyldonor), solvents with a low logP value, and fatty acids with chain lengths from C4 to C18 as acyl donors. In hydrophilic solvents such as THF and acetone, conversions of up to 99–92% were achieved after 3 h of reaction. In a more sustainable solvent such as 2-methyl-THF (2-MeTHF), high conversions were also obtained (86%). Short and medium chain acyl donors (C4–C10) allowed maximum conversions after 3 h, and long chain acyl donors (C12–C18) required longer reactions (5 h) to get 99% conversions. Furthermore, scaled up reactions are feasible without losing catalytic action and regioselectivity. In order to explain enzyme regioselectivity and its ability to accommodate ester chains of different lengths, homology modelling, docking studies and molecular dynamic simulations were performed to explain the behaviour observed.

Herein, a visible-light mediated strategy unlocking a family of cyclic β-amino carbonyl derivatives bearing three contiguous stereogenic centres is introduced. The overall reactivity relies on the performance of the substrate-catalyst complex to assist both the enantiocontrol and the photoredox tasks. This transformation led to an enantioselective [3 + 2] photocycloaddition between coordinated α,β-unsaturated acyl imidazoles and cyclopropylamine derivatives.

The use of magnetic nanoparticles in C–C coupling reactions enables the facile recovery of the catalyst under environmentally friendly conditions. Herein, the synthesis of Pd/Fe@Fe3O4 nanoparticles by the reduction of Pd2+ and oxidation of Fe on the surface of preformed Fe@Fe3O4 is reported. The nanoparticles were characterized using a variety of analytical techniques (transmission electron microscopy, Mössbauer spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction) to determine their size, structure, and chemical composition. The catalytic efficiency of these nanoparticles in classical Suzuki–Miyaura coupling reactions was investigated. The nanoparticles achieved high catalytic activity with the application of local heating by an alternating magnetic field. An investigation was conducted at identical temperatures to compare global heating with the application of an external magnetic field; magnetic heating demonstrated excellent substrate conversion in lesser time and at a lower temperature. The catalyst could also be recycled and reused three times, with ~ 30% decrease in the substrate conversion, which is most likely due to the agglomeration of the Pd nanoparticles or poisoning of the Pd catalyst. This approach, which takes advantage of the catalytic activity and magnetic susceptibility of magnetic nanoparticles, can be applied to several organic transformations to improve their efficiency, We are grateful for financial support provided by the Government of Spain through project PGC2018-095642-B-I00. In addition, A. Villacampa and L. Duque acknowledge the Community of Madrid for Predoctoral contracts PEJD-2019-PRE/IND-15356 and PEJ-2019-AI/IND-12506, respectively, co-financed by the European Social Fund through the Youth Employment Operational Program and the Youth Employment Initiative (YEI)

Nanomanipulation of molecular materials such as carbon nanotubes (CNTs) or new covalent organic frameworks (COFs) is key not only for the study of their fundamental physicochemical properties, but also for building and probing nanodevices. Therefore, we have investigated the tribological properties of oxidized MWCNTs (ox-MWCNTs) and their hybridization with COF building blocks (ox-MWCNTs@COF) adsorbed on a mica surface. We used the AFM tip to apply torsional forces on individual nanotubes. Depending on the manipulation parameters, the lateral displacements of the AFM tip slide and/or bend nanotubes enabling the direct quantification of the nanotube-mica adhesion. We found striking changes in the behaviour of the lateral force needed to manipulate each carbon nanotube variant which indicates an increased adhesion of ox-MWCNTs@COF with respect to ox-MWCNTs (∼10x). In addition, the use of the AFM tip as a mobile electrode enabled the measurement of electrical transport through individual nanotubes that revealed a rectifying behaviour of the ox-MWCNTs@COF with high resistivity, which was in contrast with the near ohmic performance of ox-MWCNTs, P. J.d.P. acknowledges support by grants from the Ministerio de Ciencia e Innovacion (FIS2017- 89549-R; “Maria de Maeztu” Program for Units of Excellence in R&D MDM2014-0377; and FIS2017-90701- REDT) and the Human Frontiers Science Program (HFSPO RGP0012/ 2018). R. M. ackowledges support by grant PID2019-110637RB-100

Porphyrinoids are considered perfect candidates for their incorporation into electron donor–acceptor (D–A) arrays due to their remarkable optoelectronic properties and low reorganization energies. For the first time, a series of subphthalocyanine (SubPc) and corrole (Cor) were covalently connected through a short-range linkage. SubPc axial substitution strategies were employed, which allowed the synthesis of the target molecules in decent yields. In this context, a qualitative synthetic approach was performed to reverse the expected direction of the different electronic events. Consequently, in-depth absorption, fluorescence, and electrochemical assays enabled the study of electronic and photophysical properties. Charge separation was observed in cases of electron-donating Cors, whereas a quantitative energy transfer from the Cor to the SubPc was detected in the case of electron accepting Cors, This work was supported by the Spanish MINECO, PID2020- 116490GB I00 (Porphyrinoids, T.T) and by the Italian PRIN MIUR “SUNSET“ 2017EKCS35_002. IMDEA-Nanociencia also acknowledges support from the “Severo Ochoa” Programme for Centres of Excellence in R&D (MINECO, Grant SEV-2016-0686)

A diastereoselective synthesis of borylated bicyclic 5-5 fused ring systems by a domino Ni-catalyzed hydroborylative polycyclization of allenynes has been developed. The reaction provides two new C−C and one C−B bonds and constitutes an atom-economical method. It occurs rapidly, in absence of inert atmosphere, with an inexpensive Ni-based catalyst and HBpin as boron source. The procedure showed excellent tolerance to functional groups and a wide scope. Derivatization of the borylated bicycles has been performed to explore the synthetic utility of the products. Experimental and DFT-calculation results suggest that the process starts by an oxidative cyclometallation involving Ni(0) and both the allene and the alkyne moieties, followed by a stereoselective σ-metathesis with HBpin. Formation of the second ring takes place through a non-fully coplanar 1,2-insertion into the Ni−H bond to give a nickelacyclohexene which finally evolves by reductive elimination. (Figure presented), We thank the support by MICIU (CTQ2016-79826-R and PID2019- 109088GB-I00) and for a FPI fellowship to I. M. M. We also thank the Centro de Computación Científica-UAM for technical assistance. We thank Juan Carlos Nieto-Carmona for helpful discussion and Prof. Fernando P. Cossío for helpful calculations

Artificial intelligence (AI) is an emerging technology that is revolutionizing the discovery of new materials. One key application of AI is virtual screening of chemical libraries, which enables the accelerated discovery of materials with desired properties. In this study, we developed computational models to predict the dispersancy efficiency of oil and lubricant additives, a critical property in their design that can be estimated through a quantity named blotter spot. We propose a comprehensive approach that combines machine learning techniques with visual analytics strategies in an interactive tool that supports domain experts’ decision-making. We evaluated the proposed models quantitatively and illustrated their benefits through a case study. Specifically, we analyzed a series of virtual polyisobutylene succinimide (PIBSI) molecules derived from a known reference substrate. Our best-performing probabilistic model was Bayesian Additive Regression Trees (BART), which achieved a mean absolute error of 5.50±0.34 and a root mean square error of 7.56±0.47, as estimated through 5-fold cross-validation. To facilitate future research, we have made the dataset, including the potential dispersants used for modeling, publicly available. Our approach can help accelerate the discovery of new oil and lubricant additives, and our interactive tool can aid domain experts in making informed decisions based on blotter spot and other key properties.

The phenanthroline unit in an imine-based covalent organic framework (Phen-COF) offers a robust coordination site for Pd(OAc)2 centers. Coordination of palladium centers is demonstrated by a variety of techniques, including X-ray photoelectron spectroscopy and total X-ray fluorescence. The stable phenanthroline-Pd(II) coordination avoids leaching of metal centers to the reaction medium, where deactivation processes through nanoparticle formation limits the catalytic activities observed for homogeneous systems. Thus, because of isolation and immobilization of catalytic sites in the Pd@Phen-COF the performance of material, the catalytic outputs are dramatically increased with respect to the performance observed for analogous molecular catalysts. This concept is applied in this work to C-C cross-coupling reactions under mild and environmentally benign conditions. The activities found for Suzuki-Miyaura and Mizoroki-Heck reactions allow thousands of turnover numbers in the transformation of a wide scope of precursors with a high degree of recyclability. The results reported in this work contribute to the design of greener protocols for transformations that have a crucial role in the industrial synthesis of high-added value fine chemicals

Electron-donating corroles (Cor) were integrated with electron-accepting phthalocyanines (Pc) to afford two different non-covalent Cor ⋅ Pc systems. At the forefront was the coordination between a 10-meso-pyridine Cor and a ZnPc. The complexation was corroborated in a combination of NMR, absorption, and fluorescence assays, and revealed association with binding constants as high as 10

Many strategies have been used to construct supramolecular hollow tubes, including helical folding of oligomers, bundling of rod-like structures, rolling-up of sheets and stacking of covalent cycles. On the other hand, controlling chirality at the supramolecular level continues attracting much interest because of its implications in future applications of porous systems. This review article covers the main examples in the literature that use simple molecular structures as chiral units for precise assembly into discrete non-covalent cyclic structures that are able to form chiral supramolecular tubular systems