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Methyl Ketones (methyl + ketone)
Kinds of Methyl Ketones Selected AbstractsAlcohols for the ,-Alkylation of Methyl Ketones and Indirect Aza-Wittig Reaction Promoted by Nickel Nanoparticles,EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 29 2008Francisco Alonso Abstract Nickel nanoparticles have been found to activate primary alcohols used for the ,-alkylation of ketones or in indirect aza-Wittig reactions. These processes involve hydrogen transfer from the alcohol to the intermediate ,,,-unsaturated ketone or imine, respectively. All these reactions are carried out in the absence of any ligand, hydrogen acceptor or base under mild reaction conditions. For the first time nickel is employed as a potential alternative to noble-metal-based catalysts in both reactions. A reaction mechanism is proposed on the basis of some deuteration experiments. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] ChemInform Abstract: Formation of Unsymmetrical 1,4-Enediones via a Focusing Domino Strategy: Cross-Coupling of 1,3-Dicarbonyl Compounds and Methyl Ketones or Terminal Aryl Alkenes.CHEMINFORM, Issue 36 2010Meng Gao Abstract Both methods can be equally applied to prepare the target compounds in high yield. [source] ChemInform Abstract: Novel Synthesis of Methyl Ketones Based on the Blaise Reaction.CHEMINFORM, Issue 42 2009H. Surya Prakash Rao Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Asymmetric Allylation of Methyl Ketones by Using Chiral Phenyl Carbinols.CHEMINFORM, Issue 41 2009Lutz F. Tietze Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis of Diketones and ,-Hydroxy Ketones from Methyl Ketones and ,,,-Diols by an [IrCl(cod)]2/PPh3/KOH System.CHEMINFORM, Issue 39 2008Kensaku Maeda Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: (S)-Pyrrolidine Sulfonamide Catalyzed Asymmetric Direct Aldol Reactions of Aryl Methyl Ketones with Aryl Aldehydes.CHEMINFORM, Issue 33 2008Shilei Zhang Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] The ,-Alkylation of Methyl Ketones with Primary Alcohols Promoted by Nickel Nanoparticles under Mild and Ligandless Conditions.CHEMINFORM, Issue 48 2007Francisco Alonso Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Microwave Assisted Rapid and Efficient Synthesis of Aryl Methyl Ketones and ,-Keto Esters Using Meldrum,s Acid.CHEMINFORM, Issue 27 2006D. H. More Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Ytterbium Triflate Promoted Tandem One-Pot Oxidation,Cannizzaro Reaction of Aryl Methyl Ketones.CHEMINFORM, Issue 32 2005Massimo Curini Abstract For Abstract see ChemInform Abstract in Full Text. [source] Unusual Reversal of Regioselectivity in Antibody-Mediated Aldol Additions with Unsymmetrical Methyl Ketones.CHEMINFORM, Issue 23 2004V. Maggiotti Abstract For Abstract see ChemInform Abstract in Full Text. [source] ChemInform Abstract: Facial-Selective Allylation of Methyl Ketones for the Asymmetric Synthesis of ,-Substituted Tertiary Homoallylic Ethers.CHEMINFORM, Issue 12 2002Lutz F. Tietze Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Asymmetric Allylation of Methyl Ketones by Using Chiral Phenyl CarbinolsCHEMISTRY - A EUROPEAN JOURNAL, Issue 25 2009Abstract To methyl or to alkyl? High induced facial selectivities and excellent yields are obtained in the allylation of aliphatic methyl ketones by using a structurally simple phenylbenzyl auxiliary to give the corresponding homoallylic ethers (see scheme). The transferred auxiliary has a very good protecting quality and can easily be removed. Novel chiral auxiliaries for the stereoselective allylation of aliphatic methyl ketones with allyltrimethylsilane and their use in the synthesis of homoallylic ethers are described. In a multicomponent domino process catalyzed by trifluoromethanesulfonic acid, the allyl moiety and the auxiliary are transferred onto the substrate to yield tertiary homoallylic ethers. The most useful auxiliary for a general application turned out to be the trimethylsilyl ether of phenyl benzyl carbinol with an induced diastereoselectivity of 90:10 using ethyl methyl ketone and 94:6 using isopropyl methyl ketone as substrates. The transferred substituted benzyl moiety has good protecting properties in subsequent transformations and can easily be removed under reductive conditions to provide the corresponding homoallylic alcohol. The origin of the high selectivity could be elucidated by identifying the relevant transition states using quantum-chemical calculations. An excellent agreement between calculated and experimentally observed selectivities was obtained assuming an oxocarbenium ion as intermediate. [source] Palladium-Catalyzed Aerobic Oxidation of Naturally Occurring Allylbenzenes as a Route to Valuable Fragrance and Pharmaceutical CompoundsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2010Luciana Abstract A palladium-catalyzed, aerobic oxidation of naturally occurring allylbenzenes, i.e., eugenol, methyleugenol, safrole, and estragole, in dimethylacetamide/water solutions under mild conditions has been developed, in which palladium(II) chloride is used in the absence of co-catalysts or special stabilizing ligands as the sole and recyclable catalyst. Methyl ketones that are important for the flavour and pharmaceutical industries have been obtained in good to excellent yields with low catalyst loadings (1,2,mol%) and high average turnover frequencies. This simple catalytic method represents an ecologically benign and economically attractive route to industrially valuable compounds starting from renewable substrates easily available from essential oils. [source] One-Pot Synthesis of 3-Substituted Isoquinolin-1-(2H)-ones and Fused Isoquinolin-1-(2H)-ones by SRN1 Reactions in DMSOEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2006Javier F. Guastavino Abstract 3-Substituted isoquinolin-1-(2H)-ones and fused isoquinolin-1-(2H)-ones have been obtained by the photostimulated SRN1 reactions of 2-iodobenzamide with the enolates of aromatic (acetophenone, 1-(benzo[d][1,3]dioxol-5-yl)ethanone, 1- and 2-naphthyl methyl ketones, and 2-, 3-, and 4-acetylpyridine), aliphatic (1-adamantyl methyl ketone), and cyclic ketones (1- and 2-indanone, ,- and ,-tetralone, and 1-benzosuberone) in DMSO. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Effects of the nature and concentration of substrates in aqueous solutions on the solubility of aroma compoundsFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2005Marco Covarrubias-Cervantes Abstract The solubility of nine aroma compounds (acetone, 2-butanone, 2-hexanone, 2-octanone, ethyl acetate, ethyl butanoate, ethyl hexanoate, n -hexanal, and n -hexanol) in both water and various aqueous solutions was measured at 25 °C using the mutual solubility method. The aqueous solutions consisted of sucrose, glucose, sorbitol, glycerol, polyethylene glycol 200, or maltodextrins at different concentrations. Aroma solubility in water decreased with increased hydrophobicity. For aroma molecules which have the same number of carbon atoms in their structure, aqueous solubility decreased as follows: aldehyde > methyl ketone > alcohol > ethyl ester. When using a group contribution method, the estimated solubility of ethyl esters and methyl ketones in water was, respectively, underestimated and overestimated. Compared to water, the solubility of the volatile molecules in aqueous solutions was higher in the aqueous polyols solutions than in the carbohydrate solutions, although solubility decreased as substrate concentration increased. Aqueous solutions properties, such as water activity, also in,uenced aroma compound solubility. Copyright © 2004 John Wiley & Sons, Ltd. [source] Conformational analysis, Part 41.JOURNAL OF PHYSICAL ORGANIC CHEMISTRY, Issue 6 2006-unsaturated carbonyl compounds, A modelling, LIS/NMR investigation of the conformations of Abstract A novel Lanthanide Induced Shift Analysis (LISA) is presented. In this analysis both the paramagnetic and the diamagnetic lanthanide induced chemical shifts are normalised separately in contrast to previous techniques in which only the paramagnetic shifts were normalised. This procedure is used together with molecular mechanics (MMFF94) and ab initio (RHF/6-31G, RHF/6-311G** and B3LYP/6-311G**) calculations to investigate s - cis/s - trans isomerism in some ,,, -unsaturated aldehydes, ketones and esters. In tiglic aldehyde 1 and trans -cinnamaldehyde 4 the s - trans conformer predominates with energy differences ,E (s - cis,s - trans) of 1.64 and 1.76,kcal/mol. In methyl vinyl ketone 2 and trans -cinnamyl methyl ketone 5 the populations of the s - cis and s - trans isomers are almost equal (,E 0.24 and 0.0,kcal/mol) and in methyl crotonate 3 and methyl trans -cinnamate 6 the s - cis conformer is more stable (,E ,0.72 and ,0.41,kcal/mol). These results are in agreement with both the MMFF94 and ab initio calculated energies for the compounds except tiglic aldehyde 1 in which all the calculated values are too large and cinnamyl ketone 5. In this compound the ab initio calculations predict the s - cis form to be more stable than the s - trans in contrast to both the MM calculations and the observed result which give both forms of equal energy. Also in both the MM and ab initio calculations phenyl substitution in the ketone (2 vs. 5) considerably stabilises the s - cis form. This is not observed in practise. In phenyl acetate 7 the B3LYP calculations give two equally stable structures, one planar one non-planar. The MMFF94 and MP2 calculations and the LIS analysis support the existence of only the non -planar conformer in solution, which is also the conformation of phenyl acetate in the crystal. Copyright © 2006 John Wiley & Sons, Ltd. [source] Preferential extractability of ,-oryzanol from dried soapstock using different solventsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2009Raj R Kumar Abstract BACKGROUND: ,-Oryzanol from rice bran has lately gained potential importance because of its proven health benefits. Thus the extractability of ,-oryzanol from the soapstock of crude rice bran oil is important from the perspective of future large-scale production, which would give value addition to this by-product obtained from the rice bran oil industry. The aim of the present study was to investigate the extraction of ,-oryzanol from the drum-dried soapstock of rice bran oil using various solvents. RESULTS: It was found that ,-oryzanol could be extracted most effectively using ethyl acetate, followed by dichloromethane and ethyl methyl ketone. All components of ,-oryzanol have an alcohol group in the ferulate portion giving rise to relatively high polarity, thereby increasing the extraction in more polar solvents efficiently. Ethyl acetate showed maximum extractability of ,-oryzanol by the Soxhlet method. To quantify ,-oryzanol, reverse phase high-performance liquid chromatography (RP-HPLC) was used for fingerprinting the ,-oryzanol analogues with respect to standard ,-oryzanol. CONCLUSION: A new RP-HPLC method for determining the individual components of ,-oryzanol has been reported that can be used for performing an online characterisation of ,-oryzanol analogues by liquid chromatography/mass spectrometry. Copyright © 2008 Society of Chemical Industry [source] Asymmetric Allylation of Methyl Ketones by Using Chiral Phenyl CarbinolsCHEMISTRY - A EUROPEAN JOURNAL, Issue 25 2009Abstract To methyl or to alkyl? High induced facial selectivities and excellent yields are obtained in the allylation of aliphatic methyl ketones by using a structurally simple phenylbenzyl auxiliary to give the corresponding homoallylic ethers (see scheme). The transferred auxiliary has a very good protecting quality and can easily be removed. Novel chiral auxiliaries for the stereoselective allylation of aliphatic methyl ketones with allyltrimethylsilane and their use in the synthesis of homoallylic ethers are described. In a multicomponent domino process catalyzed by trifluoromethanesulfonic acid, the allyl moiety and the auxiliary are transferred onto the substrate to yield tertiary homoallylic ethers. The most useful auxiliary for a general application turned out to be the trimethylsilyl ether of phenyl benzyl carbinol with an induced diastereoselectivity of 90:10 using ethyl methyl ketone and 94:6 using isopropyl methyl ketone as substrates. The transferred substituted benzyl moiety has good protecting properties in subsequent transformations and can easily be removed under reductive conditions to provide the corresponding homoallylic alcohol. The origin of the high selectivity could be elucidated by identifying the relevant transition states using quantum-chemical calculations. An excellent agreement between calculated and experimentally observed selectivities was obtained assuming an oxocarbenium ion as intermediate. [source] Ruthenium,Lewis Acid Catalyzed Asymmetric Diels,Alder Reactions between Dienes and ,,,-Unsaturated KetonesCHEMISTRY - A EUROPEAN JOURNAL, Issue 12 2007Jenny Rickerby Dr. Abstract The complex [Ru(Cp)(R,R -BIPHOP-F)(acetone)][SbF6], (R,R)- 1,a, was used as catalyst for asymmetric Diels,Alder reactions between dienes (cyclopentadiene, methylcyclopentadiene, isoprene, 2,3-dimethylbutadiene) and ,,,-unsaturated ketones (methyl vinyl ketone (MVK), ethyl vinyl ketone, divinyl ketone, ,-bromovinyl methyl ketone and ,-chlorovinyl methyl ketone). The cycloaddition products were obtained in yields of 50,90,% and with enantioselectivities up to 96,% ee. Ethyl vinyl ketone, divinyl ketone and the halogenated vinyl ketones worked best and their reactions with acyclic dienes consistently provided products with >90,% ee. ,-Chlorovinyl methyl ketone performed better than ,-bromovinyl methyl ketone. The reaction also provided a [4.3.1]bicyclic ring system in 95,% ee through an intramolecular cycloaddition reaction. Crystal structure determinations of [Ru(Cp)((S,S)-BIPHOP-F)(mvk)][SbF6], (S,S)- 1,b, and [Ru(Cp)((R,R)-Me4BIPHOP-F)(acrolein)][SbF6], (R,R)- 2,b, provided the basis for a rationalization of the asymmetric induction. [source] A Concise Synthesis of (,)-Indolizidines 209D and 209B,CHINESE JOURNAL OF CHEMISTRY, Issue 1 2009Hao WU Abstract A general stereoselective synthetic route to 5-substituted and 5,8-disubstituted indolizidine alkaloids has been developed starting from commercially available L -proline. (,)-Indolizidines 209D and 209B were efficiently synthesized in 9.8% and 14.8% overall yields in seven and five-step reactions from readily available aldehyde 3 and ketone 10, respectively. The key steps of this synthesis involve a substrate-induced asymmetric addition of ethyl lithiopropiolate to aldehyde 3 or methyl ketone 10, and a two-step one-pot hydrogenation/cyclization sequence to construct the bicyclic skeleton. [source] One-Pot Synthesis of 3-Substituted Isoquinolin-1-(2H)-ones and Fused Isoquinolin-1-(2H)-ones by SRN1 Reactions in DMSOEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 17 2006Javier F. Guastavino Abstract 3-Substituted isoquinolin-1-(2H)-ones and fused isoquinolin-1-(2H)-ones have been obtained by the photostimulated SRN1 reactions of 2-iodobenzamide with the enolates of aromatic (acetophenone, 1-(benzo[d][1,3]dioxol-5-yl)ethanone, 1- and 2-naphthyl methyl ketones, and 2-, 3-, and 4-acetylpyridine), aliphatic (1-adamantyl methyl ketone), and cyclic ketones (1- and 2-indanone, ,- and ,-tetralone, and 1-benzosuberone) in DMSO. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Effects of the nature and concentration of substrates in aqueous solutions on the solubility of aroma compoundsFLAVOUR AND FRAGRANCE JOURNAL, Issue 3 2005Marco Covarrubias-Cervantes Abstract The solubility of nine aroma compounds (acetone, 2-butanone, 2-hexanone, 2-octanone, ethyl acetate, ethyl butanoate, ethyl hexanoate, n -hexanal, and n -hexanol) in both water and various aqueous solutions was measured at 25 °C using the mutual solubility method. The aqueous solutions consisted of sucrose, glucose, sorbitol, glycerol, polyethylene glycol 200, or maltodextrins at different concentrations. Aroma solubility in water decreased with increased hydrophobicity. For aroma molecules which have the same number of carbon atoms in their structure, aqueous solubility decreased as follows: aldehyde > methyl ketone > alcohol > ethyl ester. When using a group contribution method, the estimated solubility of ethyl esters and methyl ketones in water was, respectively, underestimated and overestimated. Compared to water, the solubility of the volatile molecules in aqueous solutions was higher in the aqueous polyols solutions than in the carbohydrate solutions, although solubility decreased as substrate concentration increased. Aqueous solutions properties, such as water activity, also in,uenced aroma compound solubility. Copyright © 2004 John Wiley & Sons, Ltd. [source] Enders' SAMP-Hydrazone as Traceless Auxiliary in the Asymmetric 1,4-Addition of Cuprates to EnonesADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2010Karsten Sammet Abstract Conjugate additions of Gilman cyanocuprates to (S)- N -amino-2-(methoxymethyl)pyrrolidine (SAMP)-hydrazones 4, 5 derived from cyclic and acyclic ,,,-unsaturated ketones were investigated. A protocol utilizing copper(II) sulfate/ammonium chloride was evolved, which allowed cleavage of SAMP (S)- 1 under the hydrolysis and work-up conditions, followed by recovery of the auxiliary with ethylenediaminetetraacetic acid (EDTA). The enantioselectivity of cuprate additions was dominated for cyclic SAMP-hydrazones 4 by the cuprate alkyl substituent and the ring size, in the case of acyclic arylidene SAMP-hydrazones 5, however, by the nature of the aryl substituent. Electron-donating substituents gave poor enantiomeric excesses, whereas electron-withdrawing groups provided excellent ee values of 98,99%. The configuration of the new stereocenter was determined to be (R). Moreover, a reaction sequence was developed which integrates a tandem 1,4-addition/methylation and traceless hydrolytic cleavage of the auxiliary (S)- 1 in a one-pot reaction, resulting in enantiomerically pure methyl ketones 11,13, each of them with>99% ee. [source] Evaluation of model compounds,polypropylene film interactions by Fourier transformed infrared spectroscopy (FTIR) methodPACKAGING TECHNOLOGY AND SCIENCE, Issue 3 2008Laurent Safa Abstract The interactions of methyl esters, methyl ketones and aldehyde compounds with polypropylene (PP) film were investigated. PP film, placed on a glass vial, was immersed in aqueous solution containing a model flavour compound. After a determined time at 45°C, the PP film was analysed by Fourier transform infrared spectroscopy (FTIR), allowing us to follow the speed of sorption and to quantify its relative rate. ,,For PP films, we observed that the sorption strongly depended on the structure of sorbed molecules. For each functional group of flavour compounds, the sorption increased as the carbon chain number increased. A linear chain of 12,14 carbons favours the sorption more than a linear chain of eight carbons. ,,Concerning functions, the rate of sorption usually decreases from esters to ketones and to aldehydes. ,,High sorption was observed for flavour compounds with a low difference of solubility parameter (SP) value between the film and flavour [(,polymer , ,flavour)2 value]. Furthermore, by using the proposed thermodynamic affinity concept, represented as the contribution of three interactive molecular forces [dispersion (dd), polar (dp) and hydrogen bonding (dh)] between two SP values of film and flavour, packaging materials with high flavour preservation against sorption can be designed. ,,We have a good correlation between the kinetic sorption by FTIR and the SP concept. Copyright © 2007 John Wiley & Sons, Ltd. [source] Asymmetric Allylation of Methyl Ketones by Using Chiral Phenyl CarbinolsCHEMISTRY - A EUROPEAN JOURNAL, Issue 25 2009Abstract To methyl or to alkyl? High induced facial selectivities and excellent yields are obtained in the allylation of aliphatic methyl ketones by using a structurally simple phenylbenzyl auxiliary to give the corresponding homoallylic ethers (see scheme). The transferred auxiliary has a very good protecting quality and can easily be removed. Novel chiral auxiliaries for the stereoselective allylation of aliphatic methyl ketones with allyltrimethylsilane and their use in the synthesis of homoallylic ethers are described. In a multicomponent domino process catalyzed by trifluoromethanesulfonic acid, the allyl moiety and the auxiliary are transferred onto the substrate to yield tertiary homoallylic ethers. The most useful auxiliary for a general application turned out to be the trimethylsilyl ether of phenyl benzyl carbinol with an induced diastereoselectivity of 90:10 using ethyl methyl ketone and 94:6 using isopropyl methyl ketone as substrates. The transferred substituted benzyl moiety has good protecting properties in subsequent transformations and can easily be removed under reductive conditions to provide the corresponding homoallylic alcohol. The origin of the high selectivity could be elucidated by identifying the relevant transition states using quantum-chemical calculations. An excellent agreement between calculated and experimentally observed selectivities was obtained assuming an oxocarbenium ion as intermediate. [source] Volatile Organic Compounds from Arctic Bacteria of the Cytophaga-Flavobacterium-Bacteroides Group: A Retrobiosynthetic Approach in Chemotaxonomic InvestigationsCHEMISTRY & BIODIVERSITY, Issue 3 2005Jeroen Volatile organic compounds emitted by different marine arctic strains of the Cytophaga-Flavobacterium-Bacteroides group were investigated by using a modified closed-loop stripping apparatus (CLSA). Seven of nine strains emitted volatiles, dominated by methyl ketones, in specific patterns. The methyl ketones were aliphatic saturated, or unsaturated, and comprised 12 to 18 C-atoms, sometimes with terminal Me branches. They were identified by GC/MS, retention-index calculations, derivatization with dimethyl disulfide for CC bond location, and GC/FTIR to elucidate their uniform (Z)-configuration. The proposed structures of all methyl ketones were subsequently confirmed by synthesis, while the absolute configuration of chiral volatiles was elucidated by stereoselective synthesis. From retrobiosynthetic considerations, it was found that strain ARK10267 uses mainly valine, and strain ARK10063 mainly isoleucine for formation of starters for the ketone biosynthesis, which is correlated to fatty acid biosynthesis. Four strains (ARK10223, ARK10044, ARK10141, and ARK10146) use leucine. These separations are supported by phylogenetic affiliations based on 16S rRNA. Strain ARK10255b, in the course of this study found to be not a member of the Cytophaga-Flavobacterium-Bacteroides phylum, did not emit aliphatic ketones of medium chain length, but methionine-derived 4-(methylsulfanyl)butan-2-one and corresponding 4-(methylsulfanyl)butan-2-ol. Most of the compounds described have not been reported previously from nature. [source] Reduction and Coupling Reaction of Carbonyl Compounds by Aluminum Powder and a Small Amount of Oxalic Acid in WaterCHINESE JOURNAL OF CHEMISTRY, Issue 1 2006Shi-Zhen Yuan Abstract A convenient pinacol coupling of aromatic aldehydes and aryl methyl ketones has been achieved with high yields by aluminum powder in the presence of oxalic acid in water. However, the diastereoselectivities of pinacols were not satisfying, and most aliphatic aldehydes and diaryl ketones have been found to be unreactive under the same conditions. [source] | |||||||||||||||||||||||||