We describe efficient and flexible enantioselective syntheses of the active enantiomers of the pheromones of pine sawflies, including the species Diprion jingyuanensis, their homologs and, stereoisomers, as well as those identified from the Chinese species Diprion jingyuanensis, i.e., 126. A total of 48 compounds, including acetates 78–101 and propanoates 102–125, have been synthesized. Our general
Stereocontrol by introduction of a sulfur functional group in the asymmetric reduction of β-ketoesters with baker's yeast; preparation of optically pure 3s-hydroxydithioesters as a new chiral synthon of natural product synthesis
Asymmetric reduction of β-ketothioester derivatives with baker's yeast produced the corresponding opticallypure 3S-hydroxyethioesters, which are useful chiral building blocks in organic synthesis. The utility of the present method was demonstrated in the stereoselectivesynthesis of sex attractant of pine saw-fly, (2S,3S,7S)-5,7-dimethylpentadec-2-yl acetate from the SS-hydroxy esters.
Stereoselective synthesis of (2S,3S,7S)-3,7-dimethylpentadec-2-yl acetate and propionate, the sex pheromones of pine sawflies
作者:Zikun Wang、Qihai Xu、Weisheng Tian、Xinfu Pan
DOI:10.1016/j.tetlet.2007.06.123
日期:2007.10
The stereoselectivesynthesis of (2S,3S,7S)-3,7-dimethylpentadec-2-yl acetate (2) and propionate (3) was accomplished by utilizing the cheap and easily available chiron (R)-4-methyl-δ-valerolactone (4). The key steps were chelation-controlled addition of Gilmann reagent to chiral β-alkoxy aldehyde 12 and the Cu(I)-catalyzed coupling of Grignard reagent with bromoester 5 in the presence of NMP.
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
Transformation of Esters into 2-Substituted Allyl Halides via Tertiary Cyclopropanols: Application in the Stereoselective Synthesis of (2S,3S,7S)-3,7-Dimethyl-2-pentadecyl Acetate, the Sex Pheromone of the Pine SawflyNeodiprion sertifer
作者:Andrei V. Bekish、Konstantin N. Prokhorevich、Oleg G. Kulinkovich
DOI:10.1002/ejoc.200600481
日期:2006.11
(2S,3S,7S)-3,7-Dimethyl-2-pentadecyl acetate (ac-1), the sexpheromone of the pinesawflyNeodiprion sertifer, has been newly synthesized by the transformation of the corresponding esters 8 and 12 into 2-oxyalkyl-substituted allyl bromides 4 and 5 via tertiary cyclopropanols 6 and 7.