Synthesis of 1,4-phenylene-bis-aminomethanephosphonates: The stereochemical aspect

Abstract

The synthesis of new 1,4-phenylene-bis-(N-alkylaminomethane)-bis-phosphonates 3Aa-3Da by the addition of dialkyl or diaryl phosphites to the azomethine bond of 1,4-phenylene Schiff bases is reported. Some NMR studies on the stereochemistry of dialkyl phosphite addition to terephthalic bis-imines showing the exclusive formation of the meso-form are presented. The mechanism and the origin of such a high stereoselectivity are discussed. © 2000 John Wiley & Sons, Inc.