Convenient synthesis of both epimeric α-hydroxyaldehydes from α-hydroxydichloromethyl derivative
作者:Ken-ichi Sato、Yoshihiro Yamamoto、Hiroyuki Hori
DOI:10.1016/0040-4039(96)00432-7
日期:1996.4
The reaction of , methyl , methyl , and methyl and -α-d-glucopyranoside with n-Bu4NOH or CsOAc gave the epimeric α-hydroxyaldehyde derivatives, respectively.
The reactions of methyl 4,6-O-benzylidene-2-O-benzoyl- and -2-O-methyl-α-d-ribo-hexopyranosid-3-ulose with dichloromethyllithium gave the corresponding α-hydroxydichloromethyl derivatives in 75% and 87% yields, respectively. The structures of these products were determined by derivation into known compounds, respectively. A novel reaction of dichloromethyl derivatives with cesium acetate was found to give 3-α-hydroxyaldehyde or 3-α-acetoxyaldehyde derivative as a main product. SN2 inversion via spirochloroepoxide was suggested in this reaction by determining configuration of each product.