2006 Volume 54 Issue 11 Pages 1616-1619
The tandem and stepwise Staudinger/aza-Wittig reactions of several azides were examined in detail. The tandem reaction method (Method I) exhibited superior results in the yield of the corresponding isothiocyanates bearing an electron-withdrawing group than the conventional stepwise method (Method II) which involves the sequential treatment of the azides with triphenylphosphine and then carbondisulfide. The mechanistic consideration for both reaction methods was proposed on the basis of the 1H-NMR analyses.