The Improved Synthesis of 2-[Dimethylphenylsilyl]ethanol (DMPSE-OH) and Its Utility in Carboxyl Protection

Abstract A highly efficient, two-step synthesis of 2-(dimethylphenylsilyl)ethanol (DMPSE-OH) was developed via the Karstedt-catalyzed hydrosilylation of vinyl acetate followed by basic hydrolysis, providing the product in 76% overall yield. The utility of DMPSE-OH was demonstrated as a protecting group for carboxylic acids, including aromatic, aliphatic, and amino acid derivatives, via a Steglich-type esterification that proceeds in good to excellent yields. Deprotection of the resulting 2-(dimethylphenylsilyl)ethyl acetate was efficiently accomplished using tetrabutylammonium fluoride (TBAF). It is noteworthy, however, that this deprotection led to partial racemization of the amino acid substrates.