Asymmetric reduction of prochiral ketones using in situ generated oxazaborolidine derived from (1S,2S,3R,4R)-3-amino-7,7-dimethoxynorbornan-2-ol. An efficient synthesis of enantiopure (R)-tomoxetine
作者:Alexandre A.M. Lapis、Ângelo de Fátima、José E.D. Martins、Valentim E.U. Costa、Ronaldo A. Pilli
DOI:10.1016/j.tetlet.2004.11.052
日期:2005.1
Catalytic asymmetric reduction of prochiral ketones was examined in the presence of chiral oxazaborolidine catalyst 2 prepared in situ from (1S,2S,3R,4R)-3-amino-7,7-dimethoxynorbornan-2-ol (1). The optically active secondary alcohols were generally obtained in moderate to high enantiomeric excesses (ee 43–95%) and good yields (75–94%), except for ketones bearing electron-withdrawing groups. The methodology
在由(1 S,2 S,3 R,4 R)-3-氨基-7,7-二甲氧基降冰片烷-2-醇(1)原位制备的手性恶唑硼烷催化剂2的存在下,对前手性酮的催化不对称还原进行了研究。除带有吸电子基团的酮外,光学活性仲醇通常以中等至较高的对映体过量(ee 43–95%)和良好的收率(75–94%)获得。该方法应用于强力抗抑郁药对映体(R)-托莫西汀的合成。