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Within this perspective article, we intend to summarise definitions and terms that are often used in the context of open science and data-driven R&D and we discuss upcoming European regulations concerning data, data sharing and handling. With this background in hand, we take a closer look at the potential connections and permeable interfaces of open science and digital economy, in which data and resulting immaterial goods can become vital pieces as tradeable items. We believe that both science and the digital economy can profit from a seamless transition and foresee that the scientific outcomes of publicly funded research can be better exploited. To close the gap between open science and the digital economy, and to serve for a balancing of the interests of data producers, data consumers, and an economy around services and the public, we introduce the concept of generic research data management plans (RDMs), which have in part been developed through a community effort and which have been evaluated by academic and industry members of the NFDI4Cat consortium. We are of the opinion that in data-driven research, RDMs do need to become a vital element in publicly funded projects.

In this work we present a new concept of a millistructured capillary reactor setup for contactless kinetic measurements via in-line Raman spectroscopy for three phase reactions in single slugs. With this setup, it is possible to decouple the residence time from the volumetric flow and the reactor length. Catalysts palladium supported on carbon, in the form of Pd nano-particles on graphite fibres as well as in the form of a fixed bed catalysts as particulates of porous carbon, were utilised. A 3D-printed catalyst holder was designed to integrate the catalyst powder with a fixed bed in the capillary. The proof of concept was demonstrated using two test reactions, namely the hydrogenation of nitrobenzene and cinnamaldehyde. Multiple measurements were carried out and a good reproducibility was achieved, which lays the foundation for the application of this 3-phase oscillating droplet reactor as a tool for assessing kinetics with respect to heterogeneously catalysed three phase reactions.

Metal alkoxides are easily available and versatile precursors for functional materials, such as solid catalysts. However, the poor solubility of metal alkoxides in organic solvents usually hinders their facile application in sol–gel processes and complicates access to complex carbonate or oxidic compounds after hydrolysis of the precursors. In our contribution we have therefore shown three different solubilization strategies for metal alkoxides, namely the derivatization, the hetero-metallization and CO2 insertion. The latter strategy leads to a stoichiometric insertion of CO2 into the metal–oxygen bond of the alkoxide and the subsequent formation of metal alkyl carbonates. These precursors can then be employed advantageously in sol–gel chemistry and, after controlled hydrolysis, result in chemically defined crystalline carbonates and hydroxycarbonates. Cu- and Zn-containing carbonates and hydroxycarbonates were used in an exemplary study for the synthesis of Cu/Zn-based bulk catalysts for methanol synthesis with a final comparable catalytic activity to commercial standard reference catalysts.

Tertiary phosphines are generally known to withstand inversion under moderate conditions. In this work, a remarkable racemization process of three P‐chiral ferrocenyl phosphines is reported. Subjected to conventional column chromatography as highly enantioenriched compounds, they greatly experienced racemization when collected at the column outlet within minutes. Initially, attention was drawn to this unusual inversion behavior after observing that the superb enantiomeric excess of these ligands (>95 % ee in all cases) was almost lost in their corresponding ruthenium(II) complexes. Successively excluding possible racemization causes, these P‐chiral ferrocenyl phosphines were found to undergo a significant, acid‐catalyzed racemization process at room temperature within a few minutes. This process is mainly observed during standard column chromatography by using conventional silica or alumina, but can also be triggered deliberately by addition of certain acids. Therefore, the stereochemical preservation of P‐chiral phosphines during their purification may per se not always be guaranteed, since column chromatography is the most frequently used technique for purifying such types of compounds., Enantiomeric excess vanished! Subjected to conventional column chromatography as highly enantioenriched compounds, P‐chiral ferrocenyl phosphines suffered dramatically from racemization when collected at the column outlet even within minutes. What has happened? The authors have thoroughly investigated this most frequently used technique for the purification of such compounds and found a remarkable process as the explanation.

In the current work the tautomeric equilibrium between tetraphenyldiphosphoxane (Ph$_2$P–O–PPh$_2$, POP) and tetraphenyldiphosphine monoxide (Ph$_2$P–P([double bond, length as m-dash]O)Ph$_2$, PPO) in the absence and presence of transition metal precursors is investigated. Whereas with hard transition metal ions, such as Fe(II) and Y(III), PPO-type complexes, such as [FeCl$_2$(PPO)$_2$] and [YCl$_3$(THF)$_2$(PPO)], are formed, softer transition metals ions tend to form so-called coordination stabilised tautomers of the POP ligand form, such as [Cu$_2$(MeCN)$_3$(μ$_2$-POP)$_2$](PF$_6$)$_2$, [Au$_2$Cl$_2$(μ$_2$-POP)], and [Au$_2$(μ$_2$-POP)$_2$](OTf)$_2$. The photo-optical properties of the PPO- and POP-type transition metal complexes are investigated experimentally using photo-luminescence spectroscopy, whereby the presence of metallophillic interactions was found to play a crucial role. The dinuclear copper complex [Cu$_2$(MeCN)$_3$(μ$_2$-POP)$_2$](PF$_6$)$_2$ shows a very interesting thermochromic behavior and intense photo-luminescence with remarkable phosphoresence lifetimes at 77 K, which can probably be attributed to short intramolecular Cu–Cu distances.

The effects of moving the donor N-atom from the 2-position in lithium (2-pyridyl)- and (2-quinolyl)aluminates to the more remote position in (8-quinolyl)aluminates have been investigated by solid-state structural and DFT computational studies of the new complexes [{EtAl(2-qy)3}Li(μ-X)Li(THF)3] (X = Cl/Br 62 : 38) [(1)Li(μ-X)Li(THF)3], [{(EtAl(2-qy)3)Li}2(μ-Br)]−Li(THF)4+ [{1Li}2(μ-Br)]−Li(THF)4+, [{EtAl(2-Me-8-qy)3}Li] [(2)Li], [{Me2Al(2-Me-8-qy)2}Li(THF)] [(3a)Li(THF)], [{Me2Al(6-Me-2-py)2}Li(THF)2] [(4)Li(THF)2] and [{{EtAl(2-Me-8-qy)2}2O}(Li2THF)] (5). Increasing the remoteness of the donor N-atom from the bridgehead results in large differences in the coordination of the Li+ cations by the (8-quinolyl)aluminate anions compared to 2-quinolyl or 2-pyridyl counterparts. The results are of potential interest in understanding how the coordination sites of ligands of this type can be tuned for the coordination requirements of specific metal centres.

ChemCatChem 13(14), 3223-3236 (2021). doi:10.1002/cctc.202001974 special issue: "Data Science in Catalysis", Published by WILEY-VCH Verlag, Weinheim

Producción Científica, The coordination characteristics and donor/acceptor properties of a series of 2-pyridyl substituted phosphine ligands have been investigated using structural, spectroscopic and DFT calculational studies. A range of different coordination modes are observed in Mo and W carbonyl complexes of tris-2-pyridyl-phosphine ligands of the type P(2-py’) (2-py’ = substituted or unsubstituted 2-pyridyl group), including an unprecedented example exhibiting N,N′,μ2-π coordination. DFT calculations were used to assess the relative donor/acceptor properties of a range of related 2-pyridyl-phosphine ligands with respect to PPh3 and PtBu3., Ministerio de Ciencia, Innovación y Universidades (PGC2018-096880-A-I00. AEI / FEDER, UE)

Producción Científica, The reaction of the bis(methoxy)-2-pyridyl-phosphine (MeO)2P(2-py) (1) with [Ni(MeCN)6](BF4)2 leads to the unexpected single-step reduction of NiII and the formation of a tetrahedral nickel(0) complex [{(MeO)2P(2-py-H)}2{(MeO)2P(2-py)}2Ni](BF4)2 (2). The redox activity is probably induced by the decomposition of the tetrafluoroborate anion; NMR spectroscopic studies point towards a fluoride-assisted oxidation of the 2-pyridyl-phosphine ligand, with associated reduction of the metal., Ministerio de Ciencia, Innovación y Universidades (PGC2018-096880-A-I00. AEI / FEDER, UE)

The synthesis of a range of 1,2-diphospholides can be achieved by a one-pot procedure involving the reactions of aromatic primary phosphines bearing ortho-CH2 substituents with the superbase mixture of nBuLi/Sb(NMe2)3 in the presence of the Lewis base donor TMEDA (Me2NCH2CH2NMe2). The synthesis of the parent benzo-1,2-diphospholide and the substituted derivatives 4-methoxybenzo-1,2-diphospholide, 9-methylbenzo-1,2-diphospholide, and naphtho-1,2-diphospholide are reported from readily prepared primary phosphines. Bulk synthesis of the potassium salt of the previously reported 4,6-dimethylbenzo-1,2-diphospholide anion using this route provides a convenient starting material for reactivity studies.

The hydroformylation of olefins is one of the most important homogeneously catalyzed processes in industry to produce bulk chemicals. Despite the high catalytic activities and selectivity’s using rhodium-based homogeneous hydroformylation catalysts, catalyst recovery and recycling from the reaction mixture remain a challenging topic on a process level. Therefore, technical solutions involving alternate approaches with heterogeneous catalysts for the conversion of olefins into aldehydes have been considered and research activities have addressed the synthesis and development of heterogeneous rhodium-based hydroformylation catalysts. Different strategies were pursued by different groups of authors, such as the deposition of molecular rhodium complexes, metallic rhodium nanoparticles and single-atom catalysts on a solid support as well as rhodium complexes present in supported liquids. An overview of the recent developments made in the area of the heterogenization of homogeneous rhodium catalysts and their application in the hydroformylation of short-chain olefins is given. A special focus is laid on the mechanistic understanding of the heterogeneously catalyzed reactions at a molecular level in order to provide a guide for the future design of rhodium-based heterogeneous hydroformylation catalysts.

Producción Científica, The 1:2 reaction of the Al(III) β-diketiminate dihydride [{DMPnacnac}AlH2] (DMPnacnac = HC{C(Me)N(2,6-Me2-C6H3)}2) (1) with ammonia–borane (NH3BH3) gives the new complex [{DMPnacnac}Al{NHBH)2NH}] (3), whose [HN(BHNH)2]2– dianion is isoelectronic with β-diketiminate anions., 2019-03-15, Ministerio de Economía, Industria y Competitividad - Agencia Estatal de Investigación (AEI), European Research Council (ERC) and the European Social Fund (ESF)European Social Fund (ESF), Ramón y Cajal contract (RG-R, RYC-2015–19035)

The reaction of the commercially available ammonium salt NH4BPh4 with a pyridine-activated pinacolborane species generates a boronium cation that facilitates the 1,4-selective hydroboration of pyridines in polar solvents. This catalytic reaction is amenable to a host of reactive functional groups and provides access to sterically bulky hydroboration products, previously inaccessible by metal-free routes. Further, the regioselectivity of this reaction can be altered by reducing the polarity of the reaction solvent, resulting in greater proportions of the 1,2-hydroboration product.

In the current work a range of multidentate pyridyl-phosphine ligands are synthesised with tuneable electronic and steric character, through the incorporation of a variety of alcohols into (amino)pyridyl-phosphine frameworks. The stoichiometric reactions of compounds of the type (R2N)xP(2-py)3−x (2-py = 2-pyridyl) with alkyl as well as aryl alcohols result in the formation of (alkoxy)pyridyl-phosphines (RO)xP(2-py)3−x (R = Me, 2-Bu, Ph). This synthetic procedure also allows the introduction of enantiomerically pure alcohols, like (R)-(−)-2-BuOH and (S)-(+)-2-BuOH, and as such provides a very convenient two-step route to chiral multidentate pyridyl-phosphine ligand sets. Using the bis-amino-phosphine (Et2N)2P(2-py), the stepwise introduction of alcohols enables the synthesis of racemic alkoxy-amino-phosphines (R2N)(RO)P(2-py), as well as alkoxy-phosphines (RO)2P(2-py) and therefore offers easy access to a library of different pyridyl-phosphine ligands. Coordination studies of the (amino)pyridyl-phosphines and (alkoxy)pyridyl-phosphines with copper(I) reveal that ligands with two N donor atoms form dimeric arrangements, while (PhO)2P(2-py), in-corporating only one N donor atom, shows completely different coordination behaviour.

Metal-doped polyoxotitanate (M-POT) cages have been shown to be efficient single-source precursors to metal-doped titania [TiO

Here we illustrate a new method for the rapid determination of ee’s of chiral alcohols using the thermally-stable, non-chiral lithium aluminate reagent [EtAl(6-Me-2-py)$_3$Li] (1). $\textit{In situ}$ reaction of the alcohols with 1 produces robust dimers in solution, present as diastereomeric pairs ($\textit{SS/RR}$ and $\textit{RS}$) with distinct resonances in their $^1$H and $^7$Li NMR spectra. The ee can be calculated simply from integration of the $^1$H and/or $^7$Li NMR spectra.

Introducing substituents into the 6-position of the 2-pyridyl rings of neutral tris-pyridyl phosphanes of the type P(2-py')3 (where 2-py' is a substituted 2-pyridyl ring), has a marked impact on their coordination of transition metal ions, as revealed in the current study. Whereas the unsubstituted phosphorus-bridged tris-pyridyl ligand P(2-py)3 (1) forms the sandwich cation [{P(py)3}2Fe](2+) (4) with iron(II), coordinating via all of the donor nitrogen atoms, the reaction of the methyl-substituted counterpart P(6-Me-2-py)3 (2) and FeCl2 results in the half-sandwich arrangement [{P(6-Me-2-py)3}FeCl2]·toluene (5·toluene), in which only two N-atoms of the ligand coordinate to the metal. A similar half-sandwich type complex, [{P(6-Me-2-py)3}FeCl(OTf)]·2THF (6·2THF), is obtained from reaction of 2 with Fe(OTf)2 in the presence of LiCl, only now with all three of the N-atoms of the ligand coordinated to Fe(II). The formation of a half-rather than full-sandwich complex 2 with suggests that steric clashing of the Me groups prevents the formation of sandwich-type arrangements. The reaction of [Cu(MeCN)4]PF6 with P(6-Me-2-py) (2) gives the complex [(MeCN)3Cu{P(6-Me-2-py)3}Cu(MeCN)](PF6)2 (7), in which two Cu(I) atoms are coordinated by the bridgehead P-atom and by the three N-atoms of the tris-pyridyl ligand (a unique coordination mode in this area). Overall, the results indicate that 6-Me substitution results in a promising 6-electron capping ligand for organometallic synthesis and catalysis.

A series of rare earth 3-(4′-methylbenzoyl)propanoate (mbp–) complexes [RE(mbp)3(H2O)] (RE = rare earth = Y, La, Ce, Nd, Ho, Er) have been prepared by either metathesis reactions between the corresponding rare earth chloride and Na(mbp) or protolysis of rare earth acetates by the free acid. Single-crystal X-ray diffraction studies of [RE(mbp)3(H2O)] (RE = Ce, Nd) and [Ce(mbp)3(dmso)] reveal a 1D carboxylate-bridged polymeric structure in the solid state, featuring 9-coordinate rare earth ions. X-ray powder diffraction patterns of the bulk materials indicates that all of the [RE(mbp)3(H2O)] complexes except RE = La are isomorphous. Hence, there is no structural change from the complex with RE = Ce to that with RE = Er despite the lanthanoid contraction. The 1H NMR spectra of the RE = Ho or Er complexes in (CD3)2SO show large paramagnetic shifts and broadening of the CH2 resonances, indicating the retention of substantial carboxylate coordination in solution.