An Improved Synthesis of α-Phenylseleno Arsonium Ylides

The first a-seleno arsonium ylides have been synthesized by Typical procedure for the synthesis of compound sa. To a stirred suspension ofmethoxycarbonylmethylene triphenylarsorane (4a) (0.378 g, I mmol) and triethylamine(0. I I g, 1. 1 mmol) in MeOH-Et,O (0.6 mml, v/v=l f I ) was added dropwise the solutionof phenylselenenyl iodide 2 (0.85 mmol) in MeOH-Et,O (2.8 mml, v/v=l f l) at 0 "C for14 hrs. The mixture was stirred again for 6 hrs. After the solvent in the mixture wasevaporated un…