ChemInform Abstract: Chemistry of Phosphorylmethyl Isocyanides. Part 6. cis ‐ and trans‐2‐(Isocyanomethyl) ‐5,5‐dimethyl‐2‐oxo‐4‐phenyl‐1,3,2‐dioxaphosphorinane — Synthesis and Structure of the First Chiral Isocyanomethylphosphonate Synthons.

Abstract

Both cis-2-(isocyanomethyl) -5,5-dimethyl-2-oxo-4-phenyl-upon dehydration gave 1a. Thus, both (±)-1a and (2S,4S)-(Ϫ)-1a were prepared, and their molecular structures were 1,3,2-dioxaphosphorinane (1a) and the trans epimer 1b have been prepared as potentially useful chiral isocyano-determined by single-crystal X-ray analysis. Treatment of (2S,4S)-(-)-1a with KF gave a 1:3 equilibrium mixture of the methylphosphonate synthons. 2-Methoxy-1,3,2-dioxaphosphorinanes 5 and the corresponding 2-ethoxy analog 6 were phosphorus epimers 1a and 1b, from which the predominant trans epimer (2S,4R)-(-)-1b was isolated by column prepared from 2,2-dimethyl-1-phenyl-1,3-propanediol (2) and were converted in an Arbuzov-type reaction to 2-chromatography and crystallization. (formamidomethyl)oxo-1,3,2-dioxaphosphorinane 7, which