Synlett 2006(14): 2345-2346  
DOI: 10.1055/s-2006-949619
SPOTLIGHT
© Georg Thieme Verlag Stuttgart · New York

Benzophenone Imine

Abel Crespo*
Instituto de Farmacia Industrial (IFI), Facultad de Farmacia, ­Universidad de Santiago de Compostela, Santiago de Compostela 15782, Spain
e-Mail: qoabelcg@usc.es;
Further Information

Publication History

Publication Date:
24 August 2006 (online)

Introduction

Benzophenone imine or (diphenylmethylene)amine ­(DPMA-H, 1) is a valuable reagent in organic synthesis. [1] It is a commercially available liquid which is easily prepared by addition of phenylmagnesium bromide to benzo­nitrile followed by hydrolysis with methanol [2] or by reaction of benzophenone with ammonia. [3]

Synthetic applications of 1 have been historically related to peptide chemistry, specifically as protecting group of primary amines during the preparation of optically active α-amino acids. [4] Used in conjunction with other anion-­stabilising groups, 1 provides activation for proton ­abstraction. More recently, the development of highly ­efficient tin-free palladium-catalysed amination methodologies by the groups of Buchwald [5] and Hartwig [6] ­increased its synthetic utility as convenient ammonia ­surrogate in catalysed coupling reactions.