Reaction of O,O-dialkyl alkylphosphonates with thionyl chloride. A remarkable effect of the O-(2-dialkylamino)ethyl substituent

✍ Scribed by André Pienaar; Agnes M. Modro; Tom A. Modro

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 469 KB
• Volume: 7
• Category: Article
• ISSN: 1042-7163
• DOI: 10.1002/(sici)1098-1071(199605)7:3<177::aid-hc3>3.0.co;2-7

✦ Synopsis

Reaction of dialkyl alkylphosphonates with SOCl, in the presence of DMF: reported by Maier, can serve as a convenient route to simple monoalkyl alkylphosphonochloridates, However, when a substrate contains a (2- dia1kylamino)ethyl group as one of the ester functions, the course of the reaction is determined by the nature of the N-alkyl groups. With the NMe, group present, reaction with SOCI, occurs at nitrogen, and no exchange of groups at phosphorus takes place. The NEt, group, on the other hand, directs the reaction to phosphorus, and the Maier reaction of the exchange of one ester group OR for Cl proceeds i n high yields.