Reactions in ether between methyl-lithium and diphenylketimine, or between phenyl-lithium and phenyl cyanide, give a red solution of diphenylketiminolithium, Ph,C:NLi, from which unsolvated (Ph,C:NLi), may be obtained as a yellow amorphous and presumably polymeric solid, m. p. 260" (decomp.). Diphenylketiminoltthium forms the coloured crystalline adducts Ph,C:NLi,py, m. p. 108-1 10" (red)and Ph,C:NLi,tetrahydrofuran, m. p. 127" (orange) which dissociate in benzene and deposit (Ph,C:NLi),.Phenyl cyanide and methyl-lithium give yellow amorphous (PhCMe:NLi),t, m. p. 196". t-Butyl cyanide does not react with methyl-or ethyl-lithium a t or below 20". but methyl and ethyl cyanides with these alkyl-lithium compounds cleave alkane to give amorphous insoluble highly reactive solids believed to contain >C=C=N-groups. A similarly reactive and apparently polymeric, insoluble solid results when dimethylcyanamtde and methyl-lithium react and evolve methane. NNN'N'-Tetramethylguanidine and methyl-lithium give methane and the crystalline derivative [(Me,N),C:NLi],which is dimeric in benzene (by cryoscopy) and is also soluble in ether and toluene.DESPITE their frequent occurrence as intermediates in characterised. For example, although the derivatives reactions between elemental lithium or organolithium Ph,C:NLi and PhCMeINLi were recently used by Chan compounds and unsaturated nitrogen compounds or and Rochow 2 to prepare some azomethine derivatives compounds with N-H links, relatively few amino-of silicon, germanium, and tin, the lithium compounds derivatives of lithium, R2NLi, and no azomethine were not isolated. Such derivatives pose interesting derivatives, R2C:NLi, appear to have been isolated and structural and valence problems in that, if unsolvated, 1

Reactions between R13AI and R2NH*C0.R3 (R1 = Me or Et; R3 = Me or Ph) leading to materials ( R1,AI*NR2*CO*R3), are described. 1.r.. mass, and lH n.m.r. spectroscopic details of the products are given. Cyclic 8-membered ring structures (n = 2) are proposed for these compounds in the solution phase. Cryoscopic studies support dimeric structuresfor the compounds (Me,AI.NPh*CO*Me), and (Me,AI.NBut.CO.Me), in benzene, although an X-ray crystallographic study of the former, which can also be prepared from Me3Al and PhNCO, shows a trimeric structure to be more likely in the crystal. The related sulphur compound Me,Al*NPh.CS*Me, from Me,AI and PhNCS, probably also has a similar cyclic structure in solution. Durham R2 = Me, Et, But, or Ph; IN common with many other organonietallic compoiinds,l organoaluminium compounds R1,Al t react with isocyanates R2NC0 to give products which on hydrolysis afford N-substituted acid amides R1CO-NHR2.203 The reaction could in principle involve addition of R1-A1 across either the C=N or C=O bond, giving materials (I) or (11), respectively, both of which would afford the same amide R1CO-NHR2 on hydrolysis. Largely on the [R1,AI*NR2*CO*R1] R1CO*NHR2 t (1) H2O [R1,A1O*CR1:NR2] _ + R1C(OH):NR2 I: (11) R ',A 1 R2NC0basis of the i.r. spectra of the products, Reinheckel, Jahnke, and Kretzschmar concluded that addition to the C=N bond normally occurs, giving intermediates of type (I) which were believed to exist as chain oligomers or polymers (111). They reported no molecular weight R1,Al(*NR2*CR1:O+AlR12)~*NRz*CO*R1 (111) measurements, however. Horder and Lappert $ recently showed that the products of insertion of isot Aluminium trialkyls are referred to throughout this paper by their empirical formulae R,Al, although when R is Me or Et they are dimeric in non-donor solvents.

The adducts (Me,N),C:NH,AIX, (X = Me or Et), from (Me,N),C:NH + 3 (or more) AI,X6 in hexane, are monomeric in dilute benzene solution and are believed to have a structure co-ordinated through the imino-nitrogen. They lose XH when heated, forming [(Me,N),C:NAIX,J,. for which four-membered ring structures are suggested. Although the adduct (Me,N),C:NH,AICI, does not similarly afford [(Me2N),C:NAICI,], when heated, the latter can be prepared from (Me,N),C:NLi and AICI,.1.r. spectroscopic details are given for all these new compounds.Also discussed are the l H n.m.r. spectra of the alkylaluminium compounds and the mass spectra of (Me,N),C:NH,-AICI, and [(Me,N),C:NAlEt,],.1,1,3,3-TETRAMETHYLGUANIDINE (Me,N),C:NH (I) has three potential donor sites of two distinct types, vix., the two dimethylamino-nitrogens and one imino-nitrogen.The object of this study of its interaction with some aluminium compounds was to investigate whether incorporating other potential donor sites in a molecule containing the imino-group )C=NH affected the manner of its interaction with aluminium Lewis acids. In an earlier study using diphenylketimine Ph2C:NH, ad-

Diphenylketimine and trimethylgallium form a crystalline adduct Ph,C:NH,GaMe, which a t 100" loses methane to form the azomethine derivative (Ph,C:N*GaMe,),.In the systems Ph,C:NH-GaR, (R = Et or Ph) the 1 :1 mixtures of the components are viscous liquids whose proton magnetic resonance (p.m.r.) spectra provide evidence of weak complex formation. Both systems lose R H readily a t 100-1 20' to form azomethine derivatives (Ph,C:N*GaR,)2.Features of the infrared, p.m.r., and mass spectra of these compounds are discussed.

No abstract