α-Cuprophosphonates. V. The Reaction of 3 and 4-Oxoalkane Phosphonates and Their Use in Aminoalkanephosphonic Acids Synthesis

Abstract

In connection with our synthetic work on aminoalkanephosphonic acids we needed several 3 and 4-oxoalkanephosphonates. These compounds are generally prepared by addition of a dialkylphosphite to an α,β-unsaturated ketone¹ or by condensation of the appropriate halo-ketone with a sodium dialkylphosphite²; an alternative synthesis is via the reaction of triethylphosphite with α,β-unsaturated ketones³ or with Mannich base methiodides and hydrochlorides⁴. We now wish to report another route to 3 and 4-oxoalkanephosphonates through 3 or 4-haloalk-3-ene phosphonates. When a dihaloalkene is added at low temperature to a solution of an equivalent of α-lithioalkanephosphonate in THF/hexane, the