Organocatalytic Stereoselective Synthesis of Acyclic γ-Nitrothioesters with All-Carbon Quaternary Stereogenic Centers
作者:Yukihiro Arakawa、Sven P. Fritz、Helma Wennemers
DOI:10.1021/jo500403q
日期:2014.5.2
stereoselective synthesis of acyclic thioesters bearing adjacent quaternary and tertiary stereogenic centers under mild organocatalytic conditions was developed. α-Substituted monothiomalonates (MTMs) were used as thioester enolate equivalents. They reacted cleanly with nitroolefins in the presence of 1–6 mol % of cinchona alkaloid urea derivatives, and provided access to γ-nitrothioesters with quaternary stereocenters
提出了在温和的有机催化条件下立体选择性合成带有相邻季铵和叔立体中心的无环硫酯的方法。用α-取代的单硫代丙二酸酯(MTM)作为硫酯烯酸酯等效物。它们在1–6 mol%的金鸡纳生物碱尿素衍生物存在下与硝基烯烃干净地反应,并以高收率和非对映和对映选择性提供了具有季立体中心的γ-硝基硫代酯的通道。机械研究提供了确定立体选择性的参数的见解,并表明非对映选择性可以通过MTM底物的性质来控制。三种官能团(氧酸酯,硫酯,