A Ce(OTf)3/PyBox catalyzed enantioselective Hosomi–Sakurai reaction of aldehydes with allyltrimethylsilane†
Abstract
An efficient enantioselective Hosomi–Sakurai reaction catalyzed by a chiral Ce(OTf)3/PyBox complex has been explored. In the presence of 20 mol% of a chiral catalytic complex prepared in situ from Ce(OTf)3 and 2,6-bis[(S)-4-isopropyloxazolin-2-yl]pyridine {(S)-i-Pr-PyBox} or tetraphenyl substituted (S)-i-PrPyBox, the enantioselective allylation of aldehydes with allyltrimethylsilane proceeded smoothly at room temperature and provided the homoallylic alcohols in good yield (up to 95%) and excellent enantioselectivities (up to 99%).