Convenient synthesis of pyruvate acetals of carbohydrates by coupling of trialkylsilylated diols and pyruvates
作者:Kazumi Hiruma、Jun-ichi Tamura、Sigeomi Horito、Juji Yoshimura、Hironobu Hashimoto
DOI:10.1016/s0040-4020(01)89567-3
日期:1994.1
Hexopyranoside diols, mainly 4,6-diols with alpha-gluco, beta-gluco, alpha-galacto, beta-galacto, and alpha-manno configurations could be converted effectively (40 - 74% yields), to the corresponding pyruvate acetals by the coupling of the O-trialkylsilylated, namely, O-TBDMS and/or O-TMS diols, and ethyl pyruvate in the presence of TMSOTf at temperatures between -30 degrees C and +3 degrees C. In the case of the beta-manno isomer, the anomerization of the beta-glycoside to the alpha-glycoside as well as the ring contraction of the pyranoside to the furanoside predominated.