The synthesis and reactivity of alkylaminosubstitutedmethylenediphosphonates

Reactions of diethyl phosphite with Vilsmeier reagents, (RCONRR2)-R-1/POCl3 , afforded various alkylaminosubstitutedmethylenediphosphonates in acceptab le yields, which (R = H) were then reacted with aldehydes under the conditi ons of the Wittig-Horner reaction to furnish vinylphosphonates, and which ( R = H) underwent alkylation with alkyl halides to give alkylaminosubstitute dmethylenediposphonates 8. (Z)-Vinylphosphonates could be converted to (E)- isomers in refluxing ethyl acetate. (C) 1999 John Wiley & Sons, Inc.