Silver(I)-Catalyzed Diastereoselective Synthesis of anti-1,2-Hydroxyboronates

A catalytic protocol for the diastereoselective synthesis of anti-1,2-hydroxyboronates is described. The process provides access to secondary alkyl organoborons. The deborylative 1,2-addition reactions of alkyl 1,1-diborons proceed in the presence of a silver(I) salt with either KOtBu or nBuLi as an activator. The catalytic diastereoselective protocol can be extended to aryl, alkenyl, and alkyl aldehydes with up to 99: 1 d.r.