Strict Stereocontrol by 2,4-O-Di-tert-butylsilylene Group on β-Glucuronylations
摘要:
Strict beta-controlled glucuronylations without classical neighboring-group participation were achieved by the assistance of a 2,4-O-di-tert-butylsilylene group. Comparison of activation conditions and conformational analysis indicated that the strict beta-selectivity was achieved by steric hindrance of the 2,4-O-di-tert-butylsilylene group and not by complex glycosyl intermediates.