ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Selective synthesis of E-isomers of aldoximes via a domino aza-Michael/retro-Michael reaction

Wei Chen, Wei-Guo Yu, Hai-Bo Shi, and Xiao-Yan Lu

Zhejiang Pharmaceutical College, 315100 Ningbo, China

E-mail: xiaoyanlu@yahoo.cn

Abstract: A highly stereoselective synthesis of E-isomer of aldoximes was developed through a base-catalysed domino aza-Michael/retro-Michael reaction of hydroxylamine and 2-(R-benzylidene)malononitrile. This reaction generates (E)-aldoxime diastereomer in high yields (eight examples, isolated yields of 82-93 %), excellent diastereomeric purity (diastereomeric ratio higher than 95: 5 by ¹H NMR), and proceeds under mild reaction conditions (aqueous NaOH, pH 12, room temperature, 4 h).

Keywords: isomer – aldoxime – hydroxylamine – 2-benzylidenemalononitrile

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-012-0137-3

Chemical Papers 66 (4) 308–311 (2012)