Enantioselective Epoxidation with Chiral Mn<sup>III</sup>(salen) Catalysts: Kinetic Resolution of Aryl-Substituted Allylic Alcohols
作者:Waldemar Adam、Hans-Ulrich Humpf、Konrad J. Roschmann、Chantu R. Saha-Möller
DOI:10.1021/jo010350j
日期:2001.8.1
2-dihydronaphthalen-2-ol (2c), the CH oxidation to the enone 4c proceeds enantioselectively and competes with the epoxidation. The absolute configurations of the allylic alcohols 2 and their epoxides 3 have been determined by chemical correlation or CD spectroscopy. The observed diastereo- and enantioselectivities in the epoxidation reactions are rationalized in terms of a beneficial interplay between
一组芳基取代的烯丙醇rac-2已通过手性Mn(salen *)配合物1作为催化剂和碘代苯(PhIO)作为氧源进行环氧化。烯丙醇2的一种对映异构体优先被环氧化,以生成苏糖或顺式-环氧醇3(高达80%ee)作为主要产物(dr高达> 95:5),而2的另一种对映异构体富集(高达53%ee)。在1,1-二甲基-1,2-二氢萘-2-醇(2c)的情况下,CH氧化为烯酮4c选择性地进行,并与环氧化竞争。烯丙基醇2及其环氧化物3的绝对构型已经通过化学相关性或CD光谱法确定。