4- -2,5-dimethyl-2//1,2,3-diazaphosphole, reaction with

Lithiumalkyls (R = Me, Bu, Bu ) as well as lithium diisopropylamide (R = NPr)) add readily to the P=C bond of 2,5-dimethyl-l,2,3-diazaphosphole (66) <84PS(21)97,87JOM(319)49). With methyl iodide and organotin chlorides the adduct (67) yields 4-substituted dihydro-1,2,3-diazaphospholes (68). Only in the case of reaction of methyllithium (R = Me) is lithiation at C-4 observed as a minor side reaction (Scheme 23). 

The complex shown in Scheme 236 has been synthesized by reaction of trimethylsilylimino bis(dimethylamino)-phosphorano diazaphosphole with Cp TiCl3.642 The dichloro and dimethyl phosphinimido complexes... 

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