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The document "Green Chemistry" published by the Royal Society of Chemistry features cutting-edge research on sustainable practices and innovations in the field of chemistry. The contents include critical reviews, tutorial reviews, communications, and papers covering a wide range of topics such as biochar systems, catalysts for biomass conversion, energy conversion, and storage, as well as biodegradable polymers and synthesis methods. The journal aims to connect communities, inspire new ideas, and promote environmentally friendly solutions in chemistry. [Extracted from the article]

A halide-free and metal-free strategy for the construction of C–S/Se–P(O) bonds through a three-component reaction of allylic alcohols, P(O)H compounds, and elemental sulfur/selenium is reported. This protocol eliminates the requirement for using toxic, odorous and moisture-sensitive starting materials, as well as the need for pre-functionalization of substrates. Moreover, this transformation demonstrates high compatibility with various allylic alcohols and P(O)H compounds at a strict ratio of 1 : 1 : 1. Based on controlled experiments, a reaction mechanism involving an allyl carbocation was proposed. [ABSTRACT FROM AUTHOR]

Brønsted acid catalyzed intramolecular allylic substitution reaction of secondary and tertiary allylic alcohols has been developed. A variety of 2-vinylchromans were efficiently prepared in moderate to excellent yields. The given method features wide substrate scope, operational simplicity, and mild, metal-free reaction conditions. The practicability of the method was demonstrated by a gram-scale reaction and further derivations of the product. Preliminarily studies on a catalytic asymmetric reaction were also undertaken. [ABSTRACT FROM AUTHOR]

Densities (ρ), speeds of sound (u), and viscosities (η) were derived for three distinct binary mixtures comprising allyl alcohol in conjunction with chlorinated methanes. The Exploration ranged from 303.15 K to 313.15 K, at atmospheric pressure across all composition. The empirical data from the measurements formed the foundational basis for the determination of excess molar volume, excess isentropic compressibility, viscosity deviation and excess Gibbs free energy with the activation of viscous flow. We computed partial molar and infinite dilution properties for each binary system. The results are interpreted in the forming complexes, chemical forces and specific interactions with binary mixtures. The implication drawn from the application of the Jouyban-Acree model are expounded, taking into account the mean relative deviation (MRDs) and individual relative deviation (IRD) between the calculated and experimental densities, speed of sound, and viscosities as a criterion for accuracy criterion. FTIR studies validate experimental findings in investigated mixtures. [ABSTRACT FROM AUTHOR]

Densities (ρ), speeds of sound (u), and viscosities (η) for three binary mixtures of allyl alcohol with 3-amino-propan-1-ol, 2-amino-2-methyl-propan-1-ol (aminomethyl propanol), and 1-amino propan-2-ol (isopropanol amine) were calculated at temperatures ranging from 303.15 to 313.15K and at atmospheric pressure over the entire composition range. Experimental measurements were used to calculate the excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of the activation of viscous flow. Partial molar properties and partialmolar properties at infinite dilution are also calculated. The Prigogine–Flory–Patterson (PFP) theory is applied to identify the predominant molecular interaction. The results of the Jouyban–Acree model are discussed in terms of the mean relative deviation (MRDs) and individual relative deviation (IRD) between the calculated and experimental parameters as an accuracy criterion. FTIR studies have also been added to confirm the experimental findings of the investigated mixtures. [ABSTRACT FROM AUTHOR]

Nano-assemblies such as surfactant micelles and vesicles are widely used in drug carriers, bioreactors, and gene delivery, but can also be used as catalytic systems for chemical transformations. In the current study, we introduce nano-assemblies formed by a novel sulfonate-based amphiphilic catalyst, designated Cat-2, which are responsive to acid catalyst (HBF4) and metal catalyst (Fe(BF4)2). When the amphiphilic assemblies of Cat-2 were applied for dehydrative aminations of allylic or benzylic alcohols, we obtained the desired sulfonamide or carboxamide products with reasonable to good yields (58–92%). This methodology was also applied for gram-scale synthesis of the FDA-approved drug naftifine. Cat-2 formed small micelles (∼20 nm) in water, which were transformed into large nano-assemblies (∼550 nm) upon the addition of HBF4 and Fe(BF4)2. This morphological change mainly originates from the coordination of the sulfonate group to Fe2+. The resulting Cat-2-Fe2+ assemblies contain amide groups at the hydrophilic–hydrophobic interfaces, which act as mediators for an effective proton transfer from HBF4 in a bulk solution to the alcoholic substrate in the assembly interior. As a result, the protonated alcoholic substrate undergoes dehydration to initiate a catalytic cycle for the dehydrative amination reaction. The present methodology is favorable due to its facile and green setup, cost effectiveness, and use of easily accessible and non-toxic catalysts. In addition, the current study provides insight into the design of nano-assemblies for catalyzing organic transformations. [ABSTRACT FROM AUTHOR]

Isomerisation reactions provide streamlined routes to organic compounds which are otherwise hard to directly synthesise. The most common forms are positional, geometrical or stereochemical isomerisations which involve the relocation of a double bond or a change in relative location of groups in space. In contrast, far fewer examples of structural (or constitutional) isomerisation exist where the connectivity between atoms is altered. The development of platforms capable of such rearrangement poses a unique set of challenges because chemical bonds must be selectively cleaved, and new ones formed without overall addition or removal of atoms. Here, we show that a dual catalytic system can enable the structural isomerisation of readily available allylic alcohols into more challenging‐to‐synthesise α‐arylated ketones via a H‐atom transfer initiated semi‐pinacol rearrangement. Key to our strategy is the combination of a cobalt catalyst and photocatalyst under reductive, protic conditions which allows intermediates to propagate catalytic turnover. By providing an unusual disconnection to structural motifs which are difficult to access through direct arylation, we anticipate inspiring other advanced catalytic isomerisation strategies that will further retrosynthetic logic for complex molecule synthesis. [ABSTRACT FROM AUTHOR]

Palladium‐catalyzed carbonylation of allyl alcohol to 3‐butenoic acid has been investigated. A significant effect of halide promoters, p‐tolylsulfonic acid (TsOH), water, solvents, and PPh3 concentration activity and selectivity has been studied. Detailed kinetics of this reaction was investigated in a temperature range of 363–383 K. The influence of parameters such as stirring speed, allyl alcohol, catalyst, benzyltriethylammonium chloride (BTEAC), TsOH concentrations, and CO partial pressures on the activity and selectivity has been studied. An empirical rate equation was suggested and found to be fairly consistent with observed rate data. In addition, the activation energy and kinetic parameters were evaluated. [ABSTRACT FROM AUTHOR]

In this article, polyether‐modified polysiloxanes were synthesized by the reaction of poly(methyl hydrogen siloxane) (PMHS) with Allyl alcohol polyether B‐400. FT‐IR, laser particle size analysis, hydrophilic–lipophilic balance (HLB) value test, and surface tension measurements were used to characterize its structures and properties. The results show that the control law for the HLB value of polyether‐modified polysiloxanes was obtained as follow: the HLB value increases with increasing hydrogen content of PMHS. When the polyether‐modified polysiloxanes were used to emulsify the polysiloxane, at the HLB value of 10.5, the average particle size of the emulsion was about 0.23 μm with a narrow particle size distribution. The emulsion has good emulsifying and dispersing properties, as well as excellent foam elimination and foam inhibition performance. When the cellulose nanofibrils (CNF) was used as a protective agent for the preparing of the polysiloxane defoamer, the stability of the emulsion does not affect, but its foam elimination and foam inhibition of emulsion can be further improved at the presence of CNF. The lowest surface tension of CNF‐enhanced polyether‐modified polysiloxane defoamer is about 22.4 mN m−1, which has good surface property. When the concentration of CNF‐enhanced polyether‐modified polysiloxane defoamer was 0.1 g L−1, the foam elimination time and foam inhibition time were 5.8 s and 38 min, respectively, at the temperature (80°C) and alkali environment (pH 13). [ABSTRACT FROM AUTHOR]

Chiral tertiary alcohols are an important structural motif, however, the general and efficient methodologies for their synthesis are less reported. Herein, we report a Ni(ІІ)-catalyzed asymmetric alkenylation and arylation of aryl ketones with organoborons under air via a 1,5-metalate shift strategy to obtain chiral tertiary allylic alcohols and diaryl alcohols. The reaction demonstrates good functional group tolerance and delivers chiral tertiary alcohols with good to excellent results. Furthermore, this method can be applied to the late-stage modification of drugs and the efficient synthesis of natural products. Notably, the reaction proceeds through an outer-sphere mechanism. The Ni(II) complex functions both as a Lewis acid to activate the ketone and create a chiral environment, and as coordination bridge linking the ketone and the organoboron-derived "ate" complex, facilitating the 1,5-metalate shift without forming a C-Ni bond. This approach contrasts with traditional transition metal-catalyzed nucleophilic addition reactions that involve carbon-metal bond formation. Chiral tertiary alcohols are an important structural motif, but the general methodologies for the synthesis are less reported. Herein, the authors report a Ni(ІІ)-catalyzed asymmetric alkenylation and arylation of aryl ketones with organoborons under air via a 1,5-metalate shift to obtain chiral tertiary allylic alcohols and diaryl alcohols. [ABSTRACT FROM AUTHOR]

We demonstrated that the combination of a Pd(0) catalyst and a water‐soluble TPPMS ligand has high activity for the direct arylation of readily available allylic alcohols in the Tsuji–Trost type cross‐coupling. Various organoboron reagents can be applied, enabling rapid access to the corresponding arylated products with a wide range of functional group tolerance. Kinetic studies revealed a first‐order rate dependence for the allylic alcohol, boronic acid, CsF and Pd(0)/TPPMS concentrations. A Hammett study found a slightly positive ρ value of 0.79, suggesting that a partial negative charge is generated on the aromatic ring of the aryl boronate in the rate‐determining transmetalation step. Based on several control experiments, we concluded that the transmetalation employing CsF would proceed via the oxo‐palladium mechanism. [ABSTRACT FROM AUTHOR]

A colorless, transparent thiol‐ene polymer network was developed that contains cyclic phosphazene units in the polymer chain. Hexakis (allyloxy) cyclotriphosphazene (HAP) was synthesized from the nucleophilic substitution reaction of phosphonitrilic chloride trimer and allyl alcohol. Thiol‐ene polymers (HAP‐SH) were successfully prepared without by‐products or the use of solvents through photopolymerization of the HAP and multithiol monomers with various functional group and flexible structures (e.g., 1,4‐butanedithiol (BDTH), 1,3,5‐benzenetrithiol (BTTH), trimethylolpropane tris (3‐mercaptopropionate) (TTMP) and pentaerythritol tetrakis (3‐mercaptopropionate) (PTTH)). The prepared HAP‐SH polymers showed sufficient thermal stability due to the high degree of cross‐linking. In addition, the HAP‐SH polymer films exhibited high optical transparency of over 90% in the visible region. The refractive indices of the HAP‐SH polymers measured at 637 nm were in the range of 1.5530–1.6344, and the Abbe number was calculated to be in the range of 34.5–47.1. These results are attributed to the structure of the cyclophosphazine and the polymer main chain containing aliphatic linkers with sulfur atoms. Another significant result was the transparency of the HAP‐SH polymer films in the mid‐infrared (MWIR) region. The thermal stability and excellent optical properties of the HAP‐SH polymers make them good candidates for application as a protective film for IR lenses, which are easily damaged by external factors. [ABSTRACT FROM AUTHOR]

The intermolecular interactions between allyl alcohol + short carboxylic acids (ethanoic acid, propanoic acid, and butanoic acid) binary liquid systems were studied both at the macro- and microscopic levels using a combined experimental and computational methodology. Thermo-physical properties of allyl alcohol and short carboxylic acids binary mixtures are studied at ambient atmospheric pressure over the entire composition range and at T= (303.15 K − 313.15 K). In the present study, the calculated excess/deviation properties are discussed in terms of molecular interactions of binary mixtures. The existence of the hydrogen bonding in the binary mixtures of allyl alcohol + short carboxylic acids were further confirmed by high level theoretical calculation, namely, the density functional theory (DFT-B3LYP) of 6–311++G (d,p) basis set was used to study the geometries, bond characteristics, interaction energies and of the hydrogen bonded complexes in gas phase were investigated via quantum chemical calculations [ABSTRACT FROM AUTHOR]

A cobalt-catalyzed three-component assembly of substituted aryl oximes with dienes and formaldehyde via C–H bond activation is described. This protocol affords highly regio- and chemoselective substituted homoallylic alcohols with moderate-to-excellent yields. The scope of this protocol has been extensively explored with various substituted aryl ketoximes and aldoximes. Butadiene and internally substituted dienes are also well compatible for this transformation. A plausible reaction mechanism is proposed to account for the present reaction and is supported by deuterium labeling studies. [ABSTRACT FROM AUTHOR]

The objective of this study was to explore the applicability of biocompatible quince seed mucilage hydrogel as a promising material for drug delivery systems. In this investigation, the hydrogel was synthesized through the graft copolymerization of acrylic acid and allyl polyvinyl alcohol onto quince seed mucilage in an aqueous solution under an argon atmosphere. Characterization of the synthesized hydrogel was performed using Fourier‐transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE‐SEM), and thermogravimetric analysis (TGA). Subsequently, the developed hydrogel served as a carrier for ceftriaxone antibiotic release in both distilled water and a buffer solution with a pH of 7.4. The results demonstrated an impressive encapsulation efficiency of 96.1% for ceftriaxone within the hydrogel matrix. Additionally, the adsorption properties of ceftriaxone onto the proposed hydrogel structures (I, II, and III) were theoretically investigated in the aqueous phase using Monte Carlo adsorption locator calculations in Materials Studio2017. Our findings revealed strong adsorption on structure (III) compared to structures (I and II), with respective theoretical energies of −2.836 kcal/mol, −2.840 kcal/mol, and −2.127 kcal/mol. Therefore, the proposed hydrogel structure (III) emerges as a promising candidate for drug delivery applications, emphasizing its potential as an efficient carrier system. [ABSTRACT FROM AUTHOR]

We present herein a catalytic enantioconvergent diamination of racemic allylic alcohols with the construction of two C−N bonds and 1,3‐nonadjacent stereocenters. This iridium/chiral phosphoric acid cooperative catalytic system operates through an atom‐economical borrowing hydrogen amination/aza‐Michael cascade, and converts readily available phenylenediamines and racemic allylic alcohols to 1,5‐tetrahydrobenzodiazepines in high enantioselectivity. An intriguing solvent‐dependent switch of diastereoselectivity was also observed. Mechanistic studies suggested a dynamic kinetic resolution process involving racemization through a reversible Michael addition, making the last step of asymmetric imine reduction the enantiodetermining step of this cascade process. [ABSTRACT FROM AUTHOR]

After optimization for retention of catalytic activity, 4‐chlorobenzoic acid emerged as the optimal catalyst for the aliphatic ketone Claisen rearrangement. The optimal catalyst enables a one‐pot, metal‐free, catalytic protocol from allylic alcohols to γ,δ‐unsaturated ketones. The optimized process tolerates a range of substrates, including substituents with acid‐labile protecting groups. Reaction monitoring and DFT studies of the aliphatic ketone Claisen process agree that the ultimate rearrangement step typically has the highest activation barrier. [ABSTRACT FROM AUTHOR]

Whilst catalytic ketone allylation using palladium(0) is well–precedented, nickel(0)‐catalysed equivalents of such reactions remain scarce. We report here the first nickel‐catalysed allylation of ketones which uses an easily handled and inexpensive bench‐stable Ni(II) pre‐catalyst. This method avoids generation of stoichiometric by‐products via the use of readily available allyl alcohols, rather than the esters or related derivatives which are often used in such transformations. Under the optimised conditions, 25 monoallylated ketones were obtained in 16% to 98% yield and with high selectivity for the linear (E)‐isomers. [ABSTRACT FROM AUTHOR]

A Pd(II)‐catalyzed formal [5+2] coupling‐cyclization of 2‐arylbenzaldehydes with allylic alcohols has been developed. The method provides an efficient approach to access diaryl‐fused cycloheptene skeletons via traceless α‐amino acid‐assisted Csp2−H activation process. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed asymmetric α‐allylation of ketones is a particularly useful tool for constructing stereocenters via C−C bond formation. However, this type of reaction often necessitated the use of activated ketones or pre‐prepared enol intermediates as substrates. In this study, we developed a nickel‐catalyzed α‐allylation of unactivated cycloketones with allylic alcohols to synthesize chiral cycloketones with an α‐quaternary carbon center. The reaction affords the products with 42–97% yields, 72–86% ee, and no additive is needed, and the only by‐product is water. [ABSTRACT FROM AUTHOR]

Bimetallic Ru–Ir/Rh complexes with the Ru-based metalloligand cis-(bpy)2Ru(PPh2)2 (RuP2) serve as catalysts for the selective reduction of allyl alcohol to propylene, employing H2 gas or an electrochemical setup. Metal–metal bonded key π-allyl intermediates [(RuP2)M(η3-C3H5)]2+ (M = Ir, Rh) are identified, advancing the understanding of the catalytic processes. [ABSTRACT FROM AUTHOR]

The regiospecific Cα−Cβ cleavage of allylic alcohols under modified aerobic Mukaiyama hydration conditions is presented. The new methodology can be regarded as an equivalent of a two‐step process, a typical hydration of the parent allylic alcohol followed by a 1,2‐diol cleavage. A broad scope of substrates, both cyclic and acyclic, are applicable, thus introducing substantial structural modification to the core, especially of the former type of substrates. Mechanistic investigation of the reaction reveals the importance of the nearby hydroxyl group for the deviation from the typical Mukaiyama hydration pathway. [ABSTRACT FROM AUTHOR]

Chiral allylic alcohols are highly prized in synthetic chemistry due to their versatile reactivity stemming from both alkenyl and hydroxyl functionalities. While the Nozaki–Hiyama–Kishi (NHK) reaction is a widely used method for the synthesis of allylic alcohols, it suffers from drawbacks such as the use of toxic chromium salts, high amounts of metal reductants, and poor enantiocontrol. To address these limitations, we present a novel approach involving a metallaphotoredox‐catalyzed asymmetric NHK reaction for the production of chiral allylic alcohols. This method marries alkenyl (pseudo)halides with aldehydes, leveraging a synergistic blend of a chiral nickel catalyst and a photocatalyst. This innovative technique enables both oxidative addition and insertion just using nickel, diverging significantly from the conventional NHK reaction pathway mediated by nickel and chromium salts. The adoption of this methodology holds immense promise for crafting a spectrum of intricate compounds, particularly those of significance in pharmaceuticals. Detailed experimental investigations have shed light on the metallaphotoredox process, further enhancing our understanding and enabling further advancements. [ABSTRACT FROM AUTHOR]

The strasseriolide macrolides show promising in vitro and in vivo activities against P. falciparum and T. cruzi, the parasites causing malaria and Chagas disease, respectively. However, the as yet poor understanding of structure/activity relationships and the fact that one family member proved systemically toxic for unknown reasons render a more detailed assessment of these potential lead compounds difficult. To help overcome these issues, a collective total synthesis was devised. The key steps consisted of a ring closing alkyne metathesis (RCAM) reaction to forge a common macrocyclic intermediate followed by a hydroxy‐directed ruthenium catalyzed trans‐hydrostannation of the propargyl alcohol site thus formed. The resulting alkenyltin derivative served as the central node of the synthesis blueprint, which could be elaborated into the natural products themselves as well as into a set of non‐natural analogues according to the concept of diverted total synthesis. The recorded biological data confirmed the potency of the compounds and showed the lack of any noticeable cytotoxicity. The "northern" allylic alcohol subunit was recognized as an integral part of the pharmacophore, yet it provides opportunities for chemical modification. [ABSTRACT FROM AUTHOR]

This study examined the stability of methane hydrate at a concentration of 20 mass % in aqueous solutions of allyl and propargyl alcohols. The research determined the position of the three-phase equilibrium «alcohol solution - hydrate - gas» in the pressure range of 3.68 to 9.53 MPa. A comparison of the data revealed that the equilibrium conditions for hydrate formation for both alcohols are the same at lower pressures. However, at higher pressures, the curve for allyl alcohol deviates towards lower temperatures by 0.6°C. The study found that these alcohols act as thermodynamic inhibitors of hydrate formation. From a practical viewpoint, these systems can be used in the gas industry to prevent hydrate formation and address issues related to formed hydrates. [ABSTRACT FROM AUTHOR]

Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy for activation of viscous flow for binary mixtures of allyl alcohol (AA) with 2-methyl-2-butanol (2M2B), 2-methyl-1-butanol (2M1B) and 3-methyl-2-butanol (3M1B) components in different compositions were determined from the measured values of densities (ρ), viscosities (η) and speeds of sound (u) of pure components and their mixtures at various temperatures ranging from 303.15 K to 313.15 K. The excess properties have been discussed in terms of disruption of H-bonding and dipole–dipole interaction between the components of the mixtures. The Jouyban–Acree model results are discussed in terms of mean relative deviation (MRD) and individual relative deviation (IRD) between calculated and experimental parameters as an accuracy criterion and obtained a good agreement. The thermodynamic functions of activation of viscous flow have been estimated and tested. FTIR studies further confirm the experimental findings. [ABSTRACT FROM AUTHOR]

Temperature-responsive drug delivery systems offer the chance to better deliver anti-tumor drugs to tumor cells in a more controllable condition. In this work, a novel temperature-responsive nanocarrier was synthesized by grafting allyl alcohol and N-isopropyl acrylamide onto a nanodiamond surface and conjugated with polyester dendrimer for the controlled delivery of paclitaxel and photo-thermal therapy under near-infrared light irradiation. The morphology, chemical structure, and properties of this polymer were characterized through systematic characterization analyses. The data obtained from the non-linear isotherm model indicated that the sorption procedure followed Langmuir isotherm. Adsorption kinetic data shown that the pseudo-second-order model fitted well with the experimental results. The in-vitro drug release shown that about 92.10% of paclitaxel release was found to be occurred at the simulated physiological fluid within 48 h (pH 7.4; T = 45 °C), whereas about 64.38% of paclitaxel release occurred at the temperature of 37 °C (pH 7.4). Also, the released drug under near-infrared light irradiation reached up to 97.34% over 15 min, achieving the on-demand paclitaxel release. The release of the drug from the nanocarrier followed the mechanism of non-Fickian diffusion and best fitted to the Korsmeyer–Peppas model. The nanocarrier indicated dose dependent cytotoxicity towards MCF-7 cancer cells. [ABSTRACT FROM AUTHOR]

We report a photochemical method for the semipinacol rearrangement of unactivated allylic alcohols. Aliphatic as well as aromatic groups participate as migrating groups, yielding a variety of α,α‐disubstituted ketones. The reaction proceeds under mild conditions and is compatible with ethers, esters, halides, nitriles, carbamates, and substituted arenes. The operationally simple and fully catalytic conditions prescribe 1 mol % benzothiazinoquinoxaline as organophotocatalyst, 0.5 mol % Co‐salen, and 10 mol % lutidinium triflate and, importantly, display reactivity complementary to procedures employing Brønsted acid. We showcase the utility of the protocol in late‐stage drug diversifications. [ABSTRACT FROM AUTHOR]

A direct ortho‐Csp2‐H acylalkylation of 2‐aryl‐2,3‐dihydrophthalazine‐1,4‐diones with unsubstituted and substituted allyl alcohols is achieved in high yields through Rh(III)‐catalyzed C−H bond activation process. The additional employment of Cu(OAc)2⋅2H2O as an oxidant detour the reaction towards [4+1] annulation, producing 13‐(2‐oxopropyl)‐13H‐indazolo[1,2‐b]phthalazine‐6,11‐diones in moderate yields. Interestingly, Lawesson's reagent‐mediated conditions accomplished intramolecular cyclization in ortho‐(formylalkylated)‐2,3‐dihydrophthalazine‐1,4‐diones to produce diazepino[1,2‐b]phthalazine‐diones in moderate yields. Furthermore, allyl alcohol showcased distinct reactivity in presence of different additives to produce ortho‐allylated, oxidative and non‐oxidative [4+2] annulated products. [ABSTRACT FROM AUTHOR]

Comprehensive Summary Catalytic methylative coupling of internal alkynes and aldehydes/aldimines through regioselective oxidative cyclization promoted by a phosphine–Co complex is presented. Such process constitutes an unprecedented and unique approach for Co‐catalyzed generation of metallacycles that reversed inherent regiochemical biases to furnish a wide range of allylic alcohols and allylic amides bearing a tetrasubstituted alkene in up to 98% yield with high regioselectivity, representing a novel and general strategy for reversal of substrate‐controlled regioselectivity in metal‐catalyzed oxidative cyclization. [ABSTRACT FROM AUTHOR]

A transition metal‐free synthesis of alkylidene dihydroisobenzofurans from the ortho‐alkynyl allylic alcohols is reported herein. Notably, a simple base tBuOK is utilized for the 5‐exo‐dig cyclization and double bond isomerization of ortho‐alkynyl allylic alcohols to furnish alkylidene dihydrobenzofurans with Z‐stereoselectivity under shorter reaction times. In addition, the geometry of the double bonds was confirmed by 1D Selective Gradient NOESY and 2D NMR (NOESY) analysis. Furthermore, the effectuality of the ortho‐alkynyl allylic alcohols has been shown by extending to the one‐pot synthesis of indanones via aqueous acid‐mediated hydrolysis (ring‐opening) of in‐situ formed dihydroisobenzofurans followed by intramolecular condensation reaction under acidic conditions [ABSTRACT FROM AUTHOR]

Comprehensive Summary: An asymmetric isomerization/intramolecular coupling reaction of allylic alcohols to synthesize chiral dihydrocoumarins was successfully accomplished through ruthenium catalysis. This method demonstrates a wide substrate applicability, excellent tolerance for various functional groups, and good enantioselectivities (up to 90% ee). It provides a convenient pathway to produce a diverse range of structurally distinct chiral dihydrocoumarins in good efficiency. [ABSTRACT FROM AUTHOR]

A dual cobalt and chromium photoredox-catalyzed allylation of aldehydes with allenes through a photo metal-hydride atom transfer (MHAT) process has been developed to yield homoallylic alcohols with exceptional diastereoselective control. This sustainable and efficient method holds significant promise for applications in the synthesis of valuable organic compounds. [ABSTRACT FROM AUTHOR]

Catalytic enantioselective alkenylation of aldehydes with easily accessible alkenyl halides promoted by a chiral cobalt complex derived from a newly developed tridentate bisoxazolinephosphine is presented. Such processes represent an unprecedented reaction pathway for cobalt catalysis and a general approach that enable rapid construction of highly diversified enantioenriched allylic alcohols containing a 1,1‐, 1,2‐disubstituted and trisubstituted alkene as well as axial stereogenicity in up to 99 % yield and 99 : 1 er without the need of preformation of alkenyl–metal reagents. DFT calculations revealed the origin of enantioselectivity. [ABSTRACT FROM AUTHOR]

A gold(I)‐catalyzed intramolecular dehydrative amination method has been developed to synthesize diverse cyclic sulfamides efficiently. Reactions proceed smoothly at room temperature using a combination of (IPr)AuCl (5 mol%) and AgBF4 (5 mol%). This method showcases a broad substrate scope, encompassing challenging seven‐membered ring structures, and exhibits functional group compatibility. Moreover, the reaction demonstrates high stereoselectivity, allowing the synthesis of enantiomerically enriched cyclic sulfamides from chiral secondary allylic alcohols. The synthesized cyclic sulfamides serve as valuable intermediates for generating 1,3‐diamines. This approach provides an improved route for cyclic sulfamide synthesis and a strategic entry point for obtaining essential 1,3‐diamine derivatives. [ABSTRACT FROM AUTHOR]

A domino reaction comprising four consecutive steps based on the strategy of isomerization of allylic alcohols was developed. This base‐catalyzed protocol provided an approach for constructing polysubstituted quinolines without additional additives. A wide range of di‐ or trisubstituted γ‐aminoaryl allylic alcohols bearing alkyl or (hetero)aryl substituents were transformed to a range of structurally diverse quinolines. The utility of this transformation was demonstrated by the application in the concise synthesis of several polysubstituted quinoline derivatives, including natural products and pharmacological agents. Preliminary mechanistic experiments suggest that the isomerization of γ‐aminoaryl allylic alcohol proceeds via an intramolecular 1,3‐hydrogen shift whereas for the aromatization of the dihydroquinoline intermediate two possible pathways exist: acceptorless dehydrogenation and transfer hydrogenation. [ABSTRACT FROM AUTHOR]

Cyclopropanes are among the most important structural units in natural products, pharmaceuticals, and agrochemicals. Herein, we report a manganese-catalyzed cyclopropanation of allylic alcohols with sulfones as carbene alternative precursors via a borrowing hydrogen strategy under mild conditions. Various allylic alcohols and arylmethyl trifluoromethyl sulfones work efficiently in this borrowing hydrogen transformation and thereby deliver the corresponding cyclopropylmethanol products in 58% to 99% yields. Importantly, a major benefit of this transformation is that the versatile free alcohol moiety is retained in the resultant products, which can undergo a wide range of downstream transformations to provide access to a series of functional molecules. Mechanistic studies support a sequential reaction mechanism that involves catalytic dehydrogenation, Michael addition, cyclization, and catalytic hydrogenation. Developing readily available and bench-stable reagents for the cyclopropanation of olefins is needed as traditional methodologies mainly rely on carbene-based strategies. Herein, the authors report a manganese-catalyzed cyclopropanation of allylic alcohols with sulfones via a borrowing hydrogen strategy under mild conditions. [ABSTRACT FROM AUTHOR]

3-Methyl indanones are key synthetic building blocks for a variety of natural and useful synthetic compounds. Their synthesis is exceedingly difficult. Herein, we described a palladium (II) mediated intramolecular one-pot redox-relay cyclization of aromatic homoallylic alcohols to cyclic keto compounds. This catalytic system enabled direct conversion of homoallylic alcohols to corresponding indanones (3-methyl-1-indanones). Homoallylic alcohols were synthesized by reacting allyl magnesium bromide with corresponding aromatic aldehydes. The optimized reaction yielded up to 88% 3-methylindanones. Our findings enabled us to device a plausible mechanism for this one pot reaction. [ABSTRACT FROM AUTHOR]

A visible‐light‐induced method was developed to synthesize selenylated cyclic boronic esters through intermolecular oxyselenenylation. This method can be performed under additive‐free and photocatalyst‐free conditions and generates potentially pharmaceutically useful heterocycles. A plausible reaction mechanism was proposed based on several control experiments and previous reports. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of various methods for the synthesis of substituted naphthalene derivatives. Naphthalene is a versatile organic compound with applications in materials chemistry, electronics, and medicine. The synthesis of naphthalene involves metal-catalyzed reactions, such as palladium-catalyzed carboannulation, and yields derivatives with diverse substituents. These derivatives have medicinal importance and exhibit a wide range of therapeutic activities. The article discusses different metal-catalyzed reactions, their mechanisms, and examples of reactions. It also highlights the need for more environmentally friendly approaches to naphthalene synthesis. [Extracted from the article]

A novel strategy that combines oxidative aminocatalysis and gold catalysis allows the preparation of chiral α‐quaternary isochromanes, a motif that is prevalent in natural products and synthetic bioactive compounds. In the first step, α‐branched aldehydes and propargylic alcohols are transformed into α‐quaternary ethers with excellent optical purities (>90 % ee) via oxidative umpolung with DDQ and an amino acid‐derived primary amine catalyst. Subsequent gold(I)‐catalyzed intramolecular hydroarylation affords the isochromane products with retention of the quaternary stereocenter. A second approach explores the use of allylic alcohols as reaction partners for the oxidative coupling to furnish α‐quaternary ethers with generally lower enantiopurities. Stereoretentive cyclization to isochromane products is achieved via intramolecular Friedel‐Crafts type alkylation with allylic acetates as a reactive handle. A number of synthetic elaborations and a biological study on these α‐quaternary isochromanes highlight the potential applicability of the presented method. [ABSTRACT FROM AUTHOR]

Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy for activation of viscous flow for binary mixtures of allyl alcohol (C) with benzyl aldehyde (C1), benzylamine (C2) and benzyl alcohol (C3) components in selected compositions were determined from the measured values of densities (ρ), viscosities (η) and speeds of sound (u) of pure components and their mixtures at 303.15–313.15 K. These results were analysed by different theoretical models, such as PFP and Jouyban–Acree model. The effect of various functional groups on the excess properties was discussed in terms of disruption of H-bonding and dipole–dipole interaction between the components of the mixtures. The thermodynamic results of the present investigation have been correlated with FTIR spectral studies and have obtained a good agreement. [ABSTRACT FROM AUTHOR]

A new type of catalyst containing magnesium oxide modified with various modifiers ranging from bromine and iodine, to interhalogen compounds, hydrohalogenic acids, and alkyl halides have been prepared using chemical vapor deposition (CVD) and wet impregnation methods. The obtained systems were characterized using a number of methods: determination of the concentration of X− ions, surface area determination, powder X-ray diffraction (PXRD), surface acid–base strength measurements, TPD of probe molecules (acetonitrile, pivalonitrile, triethylamine, and n-butylamine), TPD-MS of reaction products of methyl iodide with MgO, and Fourier transform infrared spectroscopy (FTIR). The catalysts’ activity and chemoselectivity during transfer hydrogenation from ethanol to acrolein to allyl alcohol was measured. A significant increase in the activity of modified MgO (up to 80% conversion) in the transfer hydrogenation of acrolein was found, while maintaining high chemoselectivity (>90%) to allyl alcohol. As a general conclusion, it was shown that the modification of MgO results in the suppression of strong basic sites of the oxide, with a simultaneous appearance of Brønsted acidic sites on its surface. Independently, extensive research on the reaction progress of thirty alkyl halides with MgO was also performed in order to determine its ability to neutralize chlorinated wastes. [ABSTRACT FROM AUTHOR]

A concise and direct Brønsted acid catalyzed cyanation of secondary and tertiary benzylic and allylic alcohols has been developed using trimethylsilyl cyanide (TMSCN) as a cyanide source and 1,1,1,3,3,3‐hexafluoro‐2‐propanol (HFIP) as a solvent. The present transition‐metal‐free catalytic process is operationally simple to perform under "open‐flask" conditions and is applicable to the preparation of a number of α‐arylacetonitriles as well as late‐stage material transformations. The effectiveness of the present protocol was further demonstrated by the first enantioselective synthesis and determination of the absolute configuration of verimol F. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) with a size range of 0.2 to 2 nm were prepared using a hydrothermal treatment of sucrose and oleic acid. The as-synthesized CDs were used to reduce H2PdCl4 to metallic Pd nanoparticles with dPd = 9.3 ± 3.7 nm, as confirmed by PXRD and HRTEM data. Pd particles were made to be larger than the CDs, to observe any inverse support effects, however, TEM data revealed that the CDs were transformed to carbon sheets in the reduction reaction at 100 °C. The synthesized Pd-CDs catalysts (0.81 wt. % loading) and CDs were both tested for the liquid phase hydrogenation of cinnamaldehyde. The influence of mass, temperature, and hydrogen flow rate on the activity and selectivity of the CDs and Pd-CDs catalyst on the hydrogenation of cinnamaldehyde was investigated. The CDs gave a cinnamaldehyde conversion (40%, 4 h) with selectivity towards the reduction of the C = O bond (cinnamyl alcohol) while the Pd-carbon catalyst was only selective to the reduction of the C = C bond (conversion 78%) indicating the dominance of Pd in the reaction. Post analysis of the deactivated catalysts indicated formation of carbon sheets and sintering of the Pd nanoparticles. It is thus shown that the presence of Pd induces the CDs to carbon sheet formation and thus indicates the limited use of CDs as a support for the olefin hydrogenation reaction with the CDs produced carbon support. This finding has implications for other studies using CDs as supports. [ABSTRACT FROM AUTHOR]

A novel strategy has been developed for the synthesis of 2,3‐diarylindanones and 2‐arylindenes through the formation of trisubstituted α,β‐unsaturated esters by the ring opening of 2,3‐diarylcyclopropenones in the presence of a catalytic amount of TPP under mild reaction conditions. Initially, PPh3 activates the diarycyclopropenone to generate the phosphonium adduct, which simultaneously reacts with 4‐hydroxycoumarins to afford α,β‐unsaturated esters instead of Wittig olefination. Subsequently, these α,β‐unsaturated esters undergo a smooth Friedel–Crafts‐type cyclization with arenes in the presence of AlCl3 to give a new series of 2,3‐diarylindanones in good to excellent yields. Additionally, the reduction of α,β‐unsaturated esters with NaBH4 followed by acid‐catalyzed cyclization of the resulting allylic alcohols afforded 2‐arylindenes in good yields. This is the first report on the use of α,β‐unsaturated esters as precursors for the synthesis of diarylindanones and arylindenes. [ABSTRACT FROM AUTHOR]

We disclose herein an electrochemical allylation of unactivated aldehydes and ketones with allylic alcohols. A wide variety of homoallylic alcohols can be obtained by treatment of aldehydes/ketones with allyl alcohols in a simple undivided cell at room temperature. In contrast to previous strategies using allyl organometallic reagents, allylsilicon, allylboron and allyl halides as the allylic precursors, the present method used allyl alcohols as effective surrogates, which makes it more practical and environmentally sustainable. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive report on the rhodium(III)-catalyzed C–H activation in indole from 2017 to 2022. The direct functionalization of C–H bonds offers a more sustainable and economically sensible route in organic synthesis, reducing the production of hazardous waste. Rhodium has been widely used as a catalyst for C–H functionalization due to its excellent functional group compatibility, versatility, reactivity, and selectivity. The article focuses on the utilization of Rh(III) catalyst for C–H activation of the indole moiety, which is a structurally important building block in natural products and pharmaceutical treatments. Various methods for directed C–H functionalization of indoles, such as C2 activation, alkylation, hydroarylation, and dual C–H activation reactions, are discussed. The text also discusses various methods for the synthesis of carbazole derivatives, benzo[e]indoles, and selective functionalization of indoles through C–H activation. While progress has been made in this area, there are still challenges to overcome, such as the need for harsh reaction conditions and stoichiometric metal oxidants. Continued research in this field is expected to improve reaction conditions and increase overall efficiency. [Extracted from the article]

The field of supported catalysis has experienced increased attention with respect to the development of novel architectures for immobilizing catalytic species, aiming to maintain or enhance their activity while facilitating the easy recovery and reuse of the active moiety. Dendrimers have been identified as promising candidates capable of imparting such properties to catalysts through selective functionalization. The present study details the synthesis of two polyphosphorhydrazone (PPH) dendrons, each incorporating azide or acetylene groups at the core for subsequent coupling through "click" triazole chemistry. Employing this methodology, a novel PPH Janus dendrimer was successfully synthesized, featuring ten polyethylene glycol (PEG) chains on one side of the structure and ten Ru(p-cymene) derivatives on the other. This design was intended to confer dual properties, influencing solubility modulation, and allowing the presence of active catalytic moieties. The synthesized dendrimer underwent testing in the isomerization of allyl alcohols in organic solvents and biphasic solvent mixtures. The results demonstrated a positive dendritic effect compared with model monometallic and bimetallic species, providing a proof-ofconcept for the first PPH Janus dendrimer with tested applications in catalysis. [ABSTRACT FROM AUTHOR]

Catalytic methods allowing for the reliable prediction and control of diverse regioselectivity along with the control of enantioselectivity to access different regio‐ and enantiomers by switching the least reaction parameters are one of the most attractive ways in organic synthesis, which provide access to diverse enantioenriched architectures from identical starting materials. Herein, a Co‐catalyzed regiodivergent and enantioselective reductive hydroalkylation of 1,3‐dienes with aldehydes has been achieved, furnishing different enantioenriched homoallylic alcohol architectures in good levels of enantioselectivity. The reaction features the switch of regioselectivity tuned by the selection of proton source. The use of an acid as proton source provided asymmetric 1,2‐hydroalkylation products under reductive conditions, yet asymmetric 4,3‐hydroalkylation products were obtained with silane as hydride source. This catalytic protocol allows for the access of homoallylic alcohols with two continuous saturated carbon centers in good levels of regio‐, diastereo‐, and enantioselectivity. [ABSTRACT FROM AUTHOR]