Simple Access to Elusive α-Boryl Carbanions and Their Alkylation: An Umpolung Construction for Organic Synthesis
作者:Kai Hong、Xun Liu、James P. Morken
DOI:10.1021/ja505455z
日期:2014.7.30
The reaction of 1,1-bis(pinacolboronate) esters with alkyl halides can be effected by metal alkoxides and provides a strategy for the construction of organoboronate compounds. The reaction is found to occur by alkoxide-induced deborylation and generation of a boron-stabilized carbanion.
An efficient and general method for the chemoselective synthesis of unsymmetrical gem‐diborylalkanes is reported. This method is based on a late‐stage desymmetrization through nucleophilic “trifluorination”, providing chiral gem‐diborylalkanes bearing a trifluoroborate group. The reaction offers a highly modular and diastereoselective approach towards the synthesis of gem‐diborylcyclopropanes. The