The reactions of lithium trimethysilylmethyls with isocyanides; structuresand reactions of the derived lithium 1-azaallyls, beta-diketiminates and a1-azabuta-1,3-dienyl-3-amide

The insertion of ArNC (Ar = 2,6-Me2C6H3) or (BuNC)-N-t into the Li-C bond o f [Li{C(H)(R)R'}] (R = SiMe3, R' = R or Ph) led to (i) the lithium 1-azaall yls [Li{N(R")C(R)C(H)R'}(tmen)] (6a R' = R. R" = Ar; 6b R' = Ph, R" = Ar; 6 c R' = Ph, R" = Bu-t), (ii) the lithium beta -diketiminates[Li{N(Bu-t)C(R)C (H)C(R)NBut}][(LiCHR2)(CNBut)] 1. Li{N(Ar)C(R)C(H)C(R)N(Ar)} 2 and [Li{N(Ar )C(R)C(H)C(Ph)N(R)}(tmen)] 7 (from 6a and PhCN), or (iii) the lithium amide [Li{N(Ar)C(R)C[N(Ar)]=C(H)Ph}(tmen)] 8. Treatment of the lithium beta -dik etiminates I and 2 with ZrCl4 yielded the complexes [ZrCl3{N(Bu-t)C(R)C(H)C (R)NBut}] 3 or [Zr{N(Ar)C(R)C(H)C(R)N(Ar)}Cl-2(mu -Cl)(2)-Li(OEt2)(2)] 4. w hile reaction of the lithium compounds 2 or 8 with MeOH gave in high yield the conjugate acids of the corresponding anions [HN(Ar)C(R)C(H)C(R)NAr] 5 o r [HN(Ar)C(R)C{N(Ar)}=C(H)Ph] 9. Each or the compounds 1-9 was fully charac terised by multinuclear NMR spectroscopy, mass spectrometry and microanalys is, while X-ray diffraction data are also provided for the complexes 4, 6b and 8.