Synthesis and Properties of Four-Membered Phosphorus Heterocycles-2-Fluoro-1,2λ⁵-Oxaphosphetanes

GRAPHICAL ABSTRACT

Abstract

The preparation of four-membered phosphorus(V)-heterocycles, 2-fluoro-1,2λ⁵-oxaphosphetanes, by reaction of P-fluoroylides with carbonyl compounds is described. The reaction is stereoselective and leads preferentially to the formation of threo-1,2λ⁵-oxaphosphetanes. Oxaphosphetanes were isolated as individual compounds and their structures were confirmed by ¹Н, ¹³C, and ³¹Р NMR spectra. The fluoro-1,2λ⁵-oxaphosphetanes may be easily converted to various alkenylphosphonates: allyl- or vinylphosphonates. This reaction represents a good method for the preparation of phosphorylated alkenes.

Keywords:

• 1,2λ⁵-Oxaphosphetanes
• phosphoranes
• allylphosphonates
• vinylphosphonates
• P-fluoroylides