Expanding the Field of Phosphorus‐Containing Fatty Acid Derivatives: Synthesis of 1,2‐Oxaphospholene Derivatives and Alkenyl Phosphonates from α‐Keto Allenes

Abstract

Abstract The first successful preparation of phosphorus‐containing heterocyclic fatty acid derivatives is described. Reaction of the C 18 α‐keto allene 1 and the C 18 α‐keto chloroallene 2 with trimethyl phosphite gave the 1,2‐oxaphospholene derivatives 4 and 6 , respectively. Hydrolysis of 4 and 6 furnished the corresponding alkenyl phosphonate 5 and alkenyl chlorophosphonate 7 , respectively. α‐Chloro‐α′‐keto allene 3 gave the oxaphospholene derivative 8 . The various intermediates and products were identified by a combination of spectroscopic and spectrometric techniques. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)