Novel nucleophilic addition SN2'–SN2' pathway: utilizing phosphonium salts as electrophilic agents for synthesizing new phosphine oxides of Morita–Baylis–Hillman (MBH) adducts

An efficient and practical approach has been developed for synthesizing phosphonates and phosphine oxides from Morita–Baylis–Hillman (MBH) adducts through the alkylation of trialkylphosphites and ethoxydiphenylphosphine using phosphonium salts derived from MBH as powerful alkylating agents. The alkylation proceeds via a Michaelis–Arbuzov mechanism. This regiospecific reaction combining the S N 2' + S N 2' = S N 2 pathway was conducted under refluxing in CHCl 3 , resulting in the isolation of the products in good yields.