School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom.
J Am Chem Soc. 2010 Feb 17;132(6):1828-30. doi: 10.1021/ja9100276.
Heating one of the most abundant naturally occurring inorganic chemicals (elemental sulfur) with one of the most readily available homochiral molecules (limonene) gives a one-step synthesis of a chiral sulfide which exhibits outstanding selectivities in sulfur ylide mediated asymmetric epoxidations and aziridinations. In particular reactions of benzyl and allylic sulfonium salts with both aromatic and aliphatic aldehydes gave epoxides with perfect enantioselectivities and the highest diastereoselectivities reported to date. In addition reactions with imines gave aziridines again with the highest enantioselectivities and diastereoselectivities reported to date. The reactions are scaleable, and the sulfide can be reisolated in high yield. The epoxidation has been used as the key step in a convergent and stereoselective synthesis of each of the diastereoisomers of the cinchona alkaloids, quinine and quinidine.
加热最丰富的天然存在的无机化学品之一（元素硫）与最容易获得的手性分子之一（柠檬烯），可以一步合成手性硫化物，在手性亚砜介导的不对称环氧化和氮杂环丙烷化反应中表现出优异的选择性。特别是苄基和烯丙基硫翁盐与芳香族和脂肪族醛的反应，得到了具有完美对映选择性和迄今为止报道的最高非对映选择性的环氧化物。此外，与亚胺的反应再次得到了具有迄今为止报道的最高对映选择性和非对映选择性的氮杂环丙烷。该反应具有可扩展性，并且硫化物可以以高产率重新分离。该环氧化反应已被用作金鸡纳生物碱奎宁和奎尼丁的每个非对映异构体的收敛和立体选择性合成的关键步骤。
