Synthesis of Isomeric (Methoxycarbonyl)furoyl Phosphonates and Their Reaction with Ethoxycarbonylmethylenetriphenylphosphorane

Abstract

Addition of diethyl- and diisopropyl hydrogen phosphites to isomeric (methoxycarbonyl)-2- and 3-furaldehydes in the presence of sodium ethylate or potassium fluoride led to the formation of the corresponding hydroxyphosphonates. When treated with DMSO-acetic anhydride mixture at room temperature these compounds were selectively oxidized to the corresponding furoyl phosphonates. 2-Methoxycarbonyl-3- furoyl phosphonate was synthesized via the Arbuzov reaction from 2-methoxycarbonyl-3-furoyl chloride and triethyl phosphite. The obtained isomeric (methoxycarbonyl)furoylphosphonates regardless of the structure of heterocyclic fragment react with ethoxycarbonylmethylenetriphenylphosphorane to give ethyl 3-(furyl)-3-(dialkoxyphosphoryl) acrylates with trans-location of phosphoryl and carbonyl groups against the double bond.