Spiroborate Ester-Mediated Asymmetric Synthesis of β-Hydroxy Ethers and Its Conversion to Highly Enantiopure β-Amino Ethers
作者:Kun Huang、Margarita Ortiz-Marciales、Wildeliz Correa、Edgardo Pomales、Xaira Y. López
DOI:10.1021/jo900666r
日期:2009.6.5
Borane-mediated reduction of aryl and alkyl ketones with α-aryl- and α-pyridyloxy groups affords β-hydroxy ethers in high enantiomeric purity (up to 99% ee) and in good yield, using as catalyst 10 mol % of spiroborate ester 1 derived from (S)-diphenylprolinol. Representative β-hydroxy ethers are successfully converted to β-amino ethers, with minor epimerization, by phthalimide substitution under Mitsunobu’s