Gold-Catalyzed Cyclization of <i>O</i>-Propargyl Carbamates under Mild Conditions: A Convenient Access to 4-Alkylidene-2-oxazolidinones
作者:Hans-Günther Schmalz、Stefanie Ritter、Yoshikazu Horino、Johann Lex
DOI:10.1055/s-2006-951555
日期:——
On treatment with catalytic amounts of gold(I) chloride (AuCl) and a base co-catalyst, O-propargyl carbamates smoothly undergo a 5-exo-dig cyclization at room temperature to afford 4-methylene-2-oxazolidinones in high yield. Substrates with a substituent at the alkyne terminus stereoselectively give rise to (Z)-4-alkylidene-2-oxazolidinones.
在使用催化量的氯化金(I)(AuCl)和碱助催化剂处理时,O-丙炔基氨基甲酸酯会在室温下顺利发生 5-外-消化环化反应,从而以高产率获得 4-亚甲基-2-恶唑烷酮。在炔末端具有取代基的底物可立体选择性地生成 (Z)-4- 亚烷基-2-恶唑烷酮。