Benzophenone imine is an organic compound with the formula of (C6H5)2C=NH. A pale yellow liquid, benzophenone imine is used as a reagent in organic synthesis.
Synthesis Benzophenone imine can be prepared by the thermal decomposition of benzophenone oxime: 2(C6H5)2C=NOH → (C6H5)2C=NH + (C6H5)2C=O
Benzophenone imine can also be synthesized by addition of phenylmagnesium bromide to benzonitrile followed by careful hydrolysis (lest the imine be hydrolyzed): C6H5CN + C6H5MgBr → (C6H5)2C=NMgBr (C6H5)2C=NMgBr + H2O → (C6H5)2C=NH + MgBr(OH) This method is known as Moureu-Mignonac ketimine synthesis. Yet another route to benzophenone imine involves reaction of benzophenone and ammonia.
Reactions Benzophenone imine undergoes deprotonation with alkyl lithium reagents. (C6H5)2C=NH + CH3Li → (C6H5)2C=NLi + CH4 (C6H5)2C=NLi + CH3I → (C6H5)2C=NCH3 + LiI
Primary amines can be protected as benzophenone imines, and the protected amines are stable in flash chromatography.
Buchwald-Hartwig amination involves coupling aromatic halide and amine to form carbon-nitrogen bonds with the help of palladium-based catalysts. Benzophenone imine can be used as an ammonia-equivalent in such reactions.
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