Arbuzov meets 1,2-oxaphosphetanes: transient 1,2-oxaphosphetan-2-iums as entry point to beta-halo phosphane oxides and P-containing oligomers

Abstract

Herein, we describe the synthesis of a 1,2r3 k3 -oxaphosphetane from ethylene oxide and its reactions with alkyl halides to form b-halo phosphane oxides in an Arbuzov-type reaction. When methyl triflate was used as a hard electrophile, cationic oligomerisation of 1,2-oxaphosphetanes was observed. DFT calculations indicate 1, 2-oxaphosphetan-2-iums as intermediates and reveal differences between the Arbuzov and the potential Perkow reaction pathway.