Pergamon Tetrahedron Letters 40 (1999) 3457 3460 TETRAHEDRON LETTERS Synthesis of 1-Phosphono-2-aza-l,3-dienes and their Conversion into 1-Vinyi-2-phosphonoaziridines. Christian Stevens]'* Marc Gallant and Norbert De Kimpe l)epartment qf Organic ("hemist~'. t'aculO; of.tgricultural and. lpplied Biological Sciences, ( "niversity o f Gent, ("oupure Links 653, B-9000 Gent, Belgium. Received 4 January 1999 accepted 23 February 1999 Abstract 1-Phosphono-2-aza-l.3-dienes were formed by 1.4-dehydrochlorinalion of the corresponding N-(phosphonomethyl)-~-chloroimines, and reacted smoothl 3 with diazomethane to give l-vinyl-2-phosphonoaziridines © 1999 Elsevier Science Ltd. All rights reserved. Kc~x~ords: 2-,tzadiene~: Pho.~phonoaziridines; Diazomethane Organophosphates have played a significant role in agrochemistry dtmng the past decades but have mostly been abandoned because of their acute toxicity. Recently, a lot of eflbrt has been devoted to the synthesis of organophosphonates. More specifically, a-aminophosphonates have been an important research topic because of their analogy to a-amino acids resulting in enzyme inhibitor activity [1 ]. Heterocyclic analogues of a-amino phosphonates have not been studied in detail and, therefore, we have been engaged in developing straightforward methodologies for the synthesis of azaheterocyclic organophosphonates in order to investigate their physiological properties. Recently, we reported on the synthesis of phosphonylated 2-bromomethylaziridines 121. Research Leader of the Belgian "'Fonds voor Wetenschappelijk Onderzock - Vlaanderen'" (Fund for Scientific Research - Flanders) 0040-4039/99/$ - see front matter © 1999 Elsevier Science Ltd. All rights reserved. Pll: S0040-4039(99)00422-0