Reactions of Electrochemically Generated Alkoxy Phosphonium Ions

Abstract

Reactions of alkoxy triphenylphosphonium salts (1), prepared by a simple electrochemical procedure from primary and secondary alcohols, with nucleophiles indicated that a soft nucleophile is apt to attack at the α -carbon to give the corresponding Sn2 product, while a hard one at the phosphorus atom to regenerate the original alcohol. Thermal decomposition of 1 with BF₄ ^- as counter anion has been shown to afford alkyl fluorides. One-pot dehydroxysubstitution reactions at the anomeric carbons of protected sugars has been effected via in situ decomposition of the corresponding electrochemically generated alkoxy phosphonium ions.