Squaramide-catalysed enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes
作者:Wen Yang、Da-Ming Du
DOI:10.1039/c2ob26068a
日期:——
A highly enantio- and diastereoselective sulfa-Michael addition of thioacetic acid to α,β-disubstituted nitroalkenes catalysed by a chiral squaramide organocatalyst has been described. This organocatalytic reaction at an extremely low catalyst loading (0.2 mol%) furnished synthetically useful β-nitro sulfides in excellent yields with good diastereoselectivities and high enantioselectivities (up to 94â:â6 dr, 95% ee). In addition, the catalytic reaction can be performed on a 10 gram scale, and facile transformation into taurine derivative is also presented.
在手性方酰胺有机催化剂的催化下,描述了硫代乙酸与δ±,δ²-二取代硝基烯的高对映和非对映选择性磺-迈克尔加成反应。这种有机催化反应的催化剂负载量极低(0.2 摩尔%),却能以极好的产率、良好的非对映选择性和较高的对映选择性(高达 94â:â6 dr,95% ee)合成出有用的δ-硝基硫化物。此外,该催化反应可以在 10 克的规模上进行,而且还能方便地转化为牛磺酸衍生物。