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DOI: 10.1039/A701875D (Paper) Reference Section for: Chem. Commun., 1997, 1149-1150

Isolation and structural characterisation of [{(Me3Si)2NMg[µ-OC(H)Ph2] ·(O[double bond, length as m-dash]CPh2)}2], an intermediate in the β-hydride transfer reaction between an alkyl(amido)magnesium and benzophenone

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Kenneth W. Henderson, John F. Allan and Alan R. Kennedy

Abstract

The in situ reaction of Bu2Mg with 2 mol. equiv. of (Me3Si)2NH followed by addition of Ph2CO yields the heteroleptic amide/alkoxide complex [{(Me3Si)2NMg[µ-OC(H)Ph2] ·(O[double bond, length as m-dash]CPh2)}2] 1, whereas reaction of purified [{(Me3Si)2N}2Mg] 2 with Ph2CO results in formation of the solvate [{(Me3Si)2N}2Mg·(O [double bond, length as m-dash]CPh2)2] 3, the difference being due to incomplete amination of the bis(alkyl)magnesium compound resulting in β-hydride transfer to the ketone, which is the first example of this type of transformation using an alkyl(amido)magnesium reagent.

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