Stereochemically Controlled Cyclopropanation of (<i>S</i>)-Glyceraldehyde Acetonide-Derived Olefins. Synthesis of (2<i>S</i>,1‘<i>R</i>,2‘<i>R</i>,3‘<i>R</i>)-2-(2‘,3‘-Dicarboxycyclopropyl)glycine
作者:Dawei Ma、Yeyu Cao、Yi Yang、Dongliang Cheng
DOI:10.1021/ol990598j
日期:1999.7.1
[GRAPHICS]The reactions of ethyl (dimethylsulfuranylidene)acetate or other related sulfonium ylides with olefins 1 derived from (S)-glyceraldehyde acetonide provide cyclopropanation products in good to excellent diastereoselectivity. On the basis of this reaction, a new synthetic protocol for (2S,1'R,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (L-DCG-IV), an isotype-selective agonist of metabotropic glutamate receptors, is developed.
Synthesis of (2S,1′R,2′R,3′R)-2-(2′,3′-Dicarboxycyclopropyl)-glycine via the Stereochemically Controlled Cyclopropanation of (S)-Glyceraldehyde Acetonide-Derived Enones
作者:Dawei Ma、Yeyu Cao、Wengen Wu、Yongwen Jiang
DOI:10.1016/s0040-4020(00)00677-3
日期:2000.9
The reaction of ethyl dimethylsulfonium acetate bromide with aromatic enones 5a or 5b derivedfrom (S)-glyceraldehyde acetonide under the action of DBU provides cyclopropanation products in excellent yield and good diastereoselectivity (10/1). High geometry-selectivity (>95/1) can be reached when the reaction is carried out at lower temperature in toluene. The cis-enone 5a gives better geometry-selectivity