Reaction of Hindered Trialkylsilyl Esters and Trialkylsilyl Ethers with Triphenylphosphine Dibromide: Preparation of Carboxylic Acid Bromides and Alkyl Bromides under MIld Neutral Conditions

Article abstract of DOI:10.1021/jo00375a034

A new route for a simultaneous deprotection-activation of hindered trialkylsilyl esters is described. tert-Butyldimethylsilyl, triisopropylsilyl, and tert-butyldiphenylsilyl carboxylates reacted with triphenylphosphine dibromide at room temperature in dichloromethane to give acid bromides in high yields.Reaction between hindered trialkylsilyl ethers and triphenylphosphine dibromide afforded alkyl bromides in excellent yields.The formation rate of acid bromides and alkyl bromides was increased when the reactions were carried out in the presence of a catalytic amount of ZnBr2.