Lithiated organophosphorus enamines: a new synthetic approach and the first crystal structures

Abstract

Made by a nitrile insertion/hydrogen migration process via Ph₂P(O)CH₂Li and Bu^tCN, the enamide Ph₂P(O)CH[double bond, length half m-dash]C(Bu^t)N(H)Li and its TMEDA hemisolvate exist as tetrameric and dinuclear arrangements respectively: the novel structure of the starting lithiated phosphane oxide, also in its TMEDA hemisolvated form, is shown to contain Li–C contacts of two distinct types.

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