A Functionalized Alkyldiphenylphosphine as an Efficient and Mild Reagent in CCl4-Promoted Substitution Reactions: Kinetics and Mechanism of the Reaction in CHCl3

Article abstract of DOI:10.1021/jo00231a029

(Pyrid-2-ylethyl)diphenylphosphine <(C5H4NCH2CH2)PPh2> can be used at 35-45 deg C in carbon tetrachloride-chloroform to give high yields of primary and secondary alkyl chlorides from the corresponding alcohols. The isolation of products is simplified by removal of the phosphorus-containing products by extraction into a dilute aqueous acid solution.The complex reaction was studied by 31P NMR.The rate constants based on the decay of phosphine are reported.The rapid conversion of alcohols proceeds equally via chlorination by <(C5H4NCH2CH2)PPh2Cl>CCl3 (path A) and by <(C5H4NCH2CH2)PPh2Cl>Cl (path B).The rates of formation and decay of an isobutoxyphosphonium intermediate, <(i-C4H9O)(C5H4NCH2CH2)PPh2>Cl, have been measured with 31P NMR.