Lipase-catalyzed resolution of racemic 2-alkyl substituted 1-alkanols
摘要:
(R)-2-alkyl-1-alkanols (R)-1 with high optical purities were obtained by lipase-catalyzed esterification of the racemic substrates (R,S)-1 with vinyl acetate in dichloromethane. The alcohols (R)-1 were oxidized without racemization to the corresponding carboxylic acids (R)-4. The enriched (S)-acetates (S)-3 either were saponified to the alcohols (S)-1 which are substrates for a second lipase-catalyzed transesterification to give (S)-1 in high optical purity or were racemized and applied once again in the kinetic resolution to prepare (R)-1.
“One-Pot” Reductive Lactone Alkylation Provides a Concise Asymmetric Synthesis of Chiral Isoprenoid Targets
作者:Jia Cao、Patrick Perlmutter
DOI:10.1021/ol401801g
日期:2013.9.6
An efficient method, based on nucleophilic addition to lactones followed by modified in situ Clemmensenreduction, provides a short synthetic route to chiral isoprenoid targets. The efficacy of this method has been exemplified through the synthesis of several targets including the commercial fragrance Rosaphen, the side chain of Zaragozic acid C, the cotton leaf sex pheromone, and the side chains of
Synthesis of (R,S)-10-methyloctadecanoic acid (tuberculostearic acid) and key chiral 2-methyl branched intermediates
作者:Paul A. Wallace、David E. Minnikin、Katharine McCrudden、Andrea Pizzarello
DOI:10.1016/0009-3084(94)90067-1
日期:1994.5
Tuberculostearicacid, (R)-10-methyloctadecanoic acid, is a characteristic component of pathogenic mycobacteria and related organisms. Sensitive detection of this acid in infected material allows rapid detection of mycobacterial disease. A novel, convergent synthesis of tuberculostearicacid and key chiral intermediates is described in this communication, to provide a reference compound. Racemic and
Chiral synthesis of (2s,3s,7s)-3,7-dimethylpentadecan-2-yl acetate and propionate, potential sex pheromone components of the pine saw-fly neodiprion sertifer (geoff.)
A synthesis of (2S,3S,7S)-3,7-dimethylpentadecan-2-yl acetate () and propionate () is described. (2S)-2-Methyldecan-1-yl lithium () was reacted with (3S,4S)-3,4-dimethyl-γ-butyrolactone () to yield the ketoalcohol which upon Huang-Minlon reduction furnished (2S,3S,7S)-3,7-dimethylpentadecan-2-ol (). Acylations gave the esters and . The (2S)-2-methyldecan-1-yl lithium was obtained via asymmetric synthesis
Stereoselective synthesis of 10,14-dimethyloctadec-1-ene, 5,9-dimethyloctadecane, and 5,9-dimethylheptadecane, the sex pheromones of female apple leafminer
作者:Jhillu S. Yadav、Kamakolanu Uma Gayathri、Neetipalli Thrimurtulu、Attaluri R. Prasad
DOI:10.1016/j.tet.2009.01.093
日期:2009.4
The stereoselectivesynthesis of (10R,14R)-10,14-dimethyloctadec-1-ene (1), (5R,9R)-5,9-dimethyloctadecane (2), and (5R,9R)-5,9-dimethylheptadecane (3) the sexpheromone components of female apple leafminer was accomplished by reductive elimination tosyl and isonitrile groups of dialkylated tosylmethyl isonitrile. The key steps involved were dialkylation of TosMIC with 1-iodo 2-methyl alkanes, which
Asymmetric protonation of photodienols enantioselective synthesis of (R)-2-methyl alkanols
作者:Olivier Piva、David Caramelle
DOI:10.1016/0957-4166(95)00080-9
日期:1995.4
The enantioselective synthesis of (R)-2-methyl alkanols has been carried out by diastereoselectivephotodeconjugation and subsequent reduction of unsaturated esters bearing as chiral moiety, the diacetone D-glucose group.