ISOLATION AND STRUCTURAL CHARACTERIZATION OF ME3SI)(2)NMG[MU-OC(H)PH-2]CENTER-DOT(O=CPH2))(2)], AN INTERMEDIATE IN THE BETA-HYDRIDE TRANSFER-REACTION BETWEEN AN AKLYL(AMIDO)MAGNESIUM AND BENZOPHENONE

The in situ reaction of Bu2Mg with 2 mel. equiv, of (Me3Si)(2)NH follo wed by addition of Ph2CO yields the heteroleptic amide/alkoxide comple x [{Me3Si)(2)NMg[mu-OC-(H)Ph-2].(O=CPh2)}(2)] 1, whereas reaction of p urified [{(Me3Si)(2)N}(2)Mg] 2 with Ph2CO results in formation of the solvate [{(Me3Si)(2)N)(2)Mg .(O=CPh2)(2)] 3, the difference being due to incomplete amination of the bis(alkyl)magnesium compound resulting in beta-hydride transfer to the ketone, which is the first example of this type of transformation using an alkyl(amido)magnesium reagent.