SYNTHESIS AND REACTIVITY OF STABLE SILYL-SUBSTITUTED NITRILIMINES

The reaction of chlorophosphanes and chlorosilanes with the lithium salts of the (bis(diisopropylamino)-thiophosphoranyl)-, bis(diisopropylamino)phosphanyl)-, (trimethylsilyl)-, and (triisopropylsilyl)diazomethane (1, 4, 5, 6) has been studied. Four isolable nitrilimines XCNNY (X = (iPr2N)2P(S), Y = SiiPr3, 10a; X = (iPr2N)2P, Y = SiPh3, 14a; X = (iPr2N)2P, Y = SiiPr3, 15a; X = Y = SiiPr3, 18a) and three observable nitrilimines (X = (iPr2N)2P(S), Y = SiMe3, 8a; X = (iPr2N)2P(S), Y = SiPh3, 9a; X = (iPr2N)2P, Y = SiMe3, 13a) have been obtained. The factors influencing the stability of nitrilimines are analyzed. Several examples of thermal nitrilimine-diazo rearrangements and photochemical nitrilimine-carbodiimide rearrangements are described. The regioselectivity of the reaction of the observable nitrilimines with methyl acrylate and methyl propiolate is compared to that reported for transient nitrilimines. An example of 1,3-addition of butyllithium to a nitrilimine is given.