Enantio- and chemoselective Brønsted-acid/Mg(nBu)2 catalysed reduction of α-keto esters with catecholborane†
Abstract
The first enantio- and chemoselective Brønsted-acid catalysed reduction of α-keto esters with catecholborane has been developed. The α-hydroxy esters were obtained under mild reaction conditions in virtually quantitative yields and excellent enantioselectivities. With slight modifications both enantiomers can be obtained without any loss of selectivity.