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Efficient Ni-catalyzed direct cross-couplings of benzylic alcohol derivatives with arylacetonitriles via CO activation are described. Various α-benzylated arylacetonitriles including those with functional groups can be prepared under mild reaction conditions.

A practically simple and direct α-alkylation of unactivated ketones using benzylic alcohols has been achieved. The in situ formed acetals are the key for the success of the reaction. The catalyst, silver hexafluoroantimonate(V) (AgSbF6) provides double activation by converting the ketone into an enol ether via acetal and generation of carbocationic center at the benzylic position of the benzylic alcohol. The alcohols include benzylic propargyl alcohols, cinnamyl alcohols, and diarylmethanols.

Protecting-group-independent cross-coupling of α-alkoxyalkyl- and α-acyloxyalkyltrifluoroborates with aryl and heteroaryl bromides is achieved through application of photoredox/nickel dual catalysis. Reactions occur under exceptionally mild conditions, with outstanding functional group compatibility and excellent observed tolerance of heteroarenes. This method offers expedient access to protected secondary benzylic alcohol motifs bearing benzyl, pivaloyl, and N,N-diisopropylcarbamoyl protecting groups.

The nickel-catalyzed α-benzylation of sulfones with readily available benzylic alcohol derivatives was achieved via C–O activation. The transformation was complete in 30 minutes using a simple Ni(COD)2 as a catalyst without any additional ligands. A variety of substituted sulfones including the building block for bioactive compound eletriptan were synthesized by using the strategy.

Various α-benzylated arylacetonitriles are prepared under mild conditions by Ni-catalyzed direct cross-coupling reactions of benzylic alcohol derivatives with arylacetonitriles via C—O activation.

An efficient Ni-catalyzed synthesis of (E)-olefins using the readily available benzylic alcohol derivatives and arylacetonitriles is described. This transformation should proceed via a tandem process involving nickel-catalyzed cross coupling via C-O activation and subsequent stereoselective E2 elimination.

Using trichloroisocyanuric acid as the oxidant, a broad variety of benzoates are prepared from benzylic alcohols and alkanols as well as phenols via intermediate conversion of the benzylic alcohol into the corresponding benzoyl chloride.

Oxidation of benzylic alcohol to ketone or aldehyde is one of the most challenging reactions in terms of green chemistry. We report herein that employing H2O2, catalytic amount of Br− and acid in continuous-flow system to realize oxidation of benzylic alcohols with broad substrate scope and high selectivity. More importantly, no over oxidation to acid was obtained and it showed higher selectivity to 2° hydroxyl groups rather than 1°.

Aliphatic (Ia) and benzylic alcohol (Ic) as well as their analogous thiols are subjected to the reaction with phosphites (IIa)/(IIc) under optimized conditions A) to produce synthetically important phosphonates.

Synopsis Optimizing the preservative regime for a preparation requires the antimicrobial effectiveness of several preservative combinations to be determined. In this study, three preservatives were tested: benzoic acid, sorbic acid and benzylic alcohol. Their preservative effects were evaluated using the antimicrobial preservative efficacy test (challenge-test) of the European Pharmacopeia (EP). A D-optimal mixture design was used to provide a maximum of information from a limited number of experiments. The results of this study were analysed with the help of the Design Expert® software and enabled us to formulate emulsions satisfying both requirements A and B of the EP.

The Ni-catalyzed direct C–H/C–O cross couplings of benzylic alcohol derivatives with fluorobenzenes and heteroarenes are disclosed. This transformation provides a straightforward and efficient method for the synthesis of these valuable heteroatom-containing compounds.

A key factor for a successful aerobic oxidation process is the addition of catalytic amounts of glucose to inhibit deactivation of the Pd-C catalyst.

The new natural products (+)-curcutetraol and (−)-curcutriolamide were isolated from the bacterium CNH-741 and the fungus CNC-979, isolated from marine sediment. (+)-Curcutetraol is a polar compound and contains a tertiary benzylic alcohol moiety at the single stereogenic center, which was retained without racemization by avoiding chromatography on silica. The absolute configuration of (+)-curcutetraol was determined by comparison of its experimental CD spectrum with the spectra predicted by quantum-chemical CD calculations. Phenolic bisabolane sesquiterpenoids from marine sources were previously known only from gorgonians and sponges. A short total synthesis of racemic curcutetraol has been developed. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

This method is suitable for benzylic alcohol derivatives (II), but not for simple aliphatic alcohols (e.

An efficient preparative procedure is elaborated for the biocatalytic benzylic hydroxylation of toluene substrate (Ia) leading to benzylic alcohol (IIa) in good isolated yield.

A variety of aryl ketones, benzaldehyde and benzylic alcohol derivatives smoothly undergo Ir-catalyzed ortho-silylation with H2SiEt2 followed by Ir-catalyzed dehydrogenative cyclization to give benzoxasilole derivatives in good yields.

Two routes for the preparation of 4(S)-(3,4-dichlorophenyl)-3,4-dihydro-1(2H)-naphthalenone are reported. The most efficient route generates a chiral benzylic alcohol by catalytic asymmetric oxazaborolidine reduction of a γ-ketoester that is subsequently activated and displaced in an SN2 manner with a higher order cuprate. Intramolecular Friedel-Crafts cyclization of the resulting t-butylester affords the title compound.

Several racemic 1,2-diols bearing a tertiary benzylic alcohol stereogenic center can be esterified regioselectively by vinyl acetate using lipases and esterases in organic media. With the correct choice of enzyme and if the non-phenyl substituent at the tertiary center is unsaturated, E values of > 250 can be achieved.

The total synthesis of hongconin (1) has been completed. Key steps include the metalation of a benzylic alcohol, the formation of a six-membered ring ether via a mercury-mediated cyclization, and the regioselective installation of the naphthalene ring by way of a Diels-Alder reaction

2-Aryl-2-methyloxiranes are enantioselectively hydrolyzed with microsomal epoxide hydrolase from pig liver to provide 1, 2-diols containing a tertiary benzylic alcohol stereogenic centre upto 34% enantio-meric purities.

Benzylic oxidation using a Mn-salen complex 3 as catalyst and iodosylbenzene as oxidant was found to proceed with moderate enantioselectivity to give the corresponding benzylic alcohol in solvents of high viscosity such as chlorobenzene and fluorobenzene. For example, the oxidation of 1,1-dimethylindane with 3 gave 3-hydroxy-1,1-dimethylindane of 64% ee.

[reaction: see text]. A highly effective protocol for allylation of secondary benzylic alcohol derivatives with allylsilanes in the presence of catalytic amounts of B(C6F5)3 has been developed. Some additional functionalities, such as bromo, acetoxy, and primary benzyloxy groups, were tolerated under these conditions.

Highly soluble dendritic branches with two, four, eight or 16 methanofullerene subunits at their peripheries and carboxylic acid functions at their focal points have been prepared by a convergent approach. Starting from a methanofullerene derivative possessing a tert-butyl ester function, the successive dendrimer generations were obtained by repetition of a reaction sequence involving cleavage of the tert-butyl ester moiety under acidic conditions, followed by a DCC-mediated esterification reaction with an A2B building block possessing two benzylic alcohol functions and a tert-butyl ester group. This repetitive synthetic sequence is very efficient and allowed the dendritic growth up to the fifth-generation derivative, containing 16 peripheral fullerene subunits. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

Asymmetric biaryl Suzuki coupling reactions were performed with various aryl- or naphthylhalide-bearing enantiomerically pure benzylic alcohols and aryl- or naphthylboronic acids (or esters). The stereogenic benzylic alcohol was introduced by diastereoselective reduction of the arylhalide bearing a β-keto sulfoxide. In the presence of Pd(OAc)2/CsF and dppf or PPh3 excellent yields and atropodiastereoselectivities were obtained. The absolute configurations of the biaryls were determined by X-ray crystallography and 1H NMR NOESY experiments. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

The reaction of Pictet‐Spengler was revisited, and its modified conditions were applied to develop a general methodology toward the synthesis of dihydroisocoumarins containing a no‐electron rich aromatic ring.

The total synthesis of the opioid modulator pawhuskin C has been accomplished in eight steps from methyl 3,5-dihydroxybenzoate. The key step in this sequence is a directed ortho metalation reaction conducted without protection of a benzylic alcohol and thus presumed to involve a formal dianion intermediate.

Migration of TBDMS and Boc groups from 2° alcohols to 1° alcohols during the reduction of β-hydroxy esters has been observed. Also, unusual cyclization has been noticed during tosylation of benzylic alcohol in tert-butyl ((2R)-2-hydroxy-2-phenyl ethyl)carbonate with S N 2 inversion.

A new photocleavable linker, 4,4'-bis(alkoxymethyl-3,3'-dinitro)biphenyl, is reported that undergoes photolysis at two positions to release two equivalents of primary, secondary, or benzylic alcohol in yields that are higher than those obtained from the analogous monomeric o-nitrobenzyl ethers.

A simple and effective procedure for conversion of primary, secondary, allylic and benzylic alcohols into the corresponding iodides is described using NaI/Amberlyst 15 in acetonitrile at room temperature. Selective conversion of benzylic alcohols in the presence of saturated alcohols into the corresponding benzylic iodides is achieved under these conditions.

The analysis of the volatile parts of fresh strawberry flavour is described. Among 35 substances identified, the following had not been found before in strawberries: 1 Carbonyl compounds: propanal, acrolein, crotonal, pent-2-enal, cis-hex-3-enal, pentan-2-one, and heptan-2-one. 2 Alcohols: pent-1-en-3-ol, heptan-2-ol and benzylic alcohol. 3 Esters: propyl acetate, methyl caproate, hexyl butyrate, isopropyl butyrate, ethyl crotonate and trans-hex-2-en-1-yl butyrate.