An efficient method for the synthesis of enantiopure 2,3-anti-propionate aldols involving a 3,5-syn- or anti-diol subunit through chiral borane-mediated enantioselective aldol reaction coupled with radical reduction

2,3-anti-Propionate aldols involving a 3,5-syn- or anti-diol subunit, versatile enantiopure segments available for macrolide synthesis, were prepared by a chiral oxazaborolidinone-promoted asymmetric aldol reaction with 2-bromo-1-ethoxy-2-methyl-1-trimethylsiloxyethene and the following highly anti-preferential radical debromination.