N,N-Diisopropylaminomethyllithium:  Synthesis, Oxidative Degradation, and Organoaluminum and -gallium Derivatives

N,N-Diisopropylaminomethyllithium (<BO>1</BO>) was prepared by transmetalation from Me<INF>3</INF>SnCH<INF>2</INF>NⁱPr<INF>2</INF> and n-BuLi. It was characterized by NMR spectroscopy (¹H, ¹³C, ⁷Li). Compound <BO>1</BO> crystallizes as a hexamer (LiCH<INF>2</INF>NⁱPr<INF>2</INF>)<INF>6</INF> and allowed the determination of the first solvent-free structure of an α-lithiated amine. It contains a Li<INF>6</INF> core (distorted octahedron) 6-fold capped by CH<INF>2</INF>NⁱPr<INF>2</INF> units. <BO>1</BO> is very sensitive to air-oxidation. A partially [(LiCH<INF>2</INF>NⁱPr<INF>2</INF>)<INF>4</INF>(LiOCH<INF>2</INF>NⁱPr<INF>2</INF>)<INF>2</INF> (<BO>2</BO>)] and a completely oxidized [(LiOCH<INF>2</INF>NⁱPr<INF>2</INF>)<INF>6</INF> (<BO>3</BO>)] cluster compound could be isolated. <BO>2</BO> and <BO>3</BO> were characterized by multinuclear NMR spectroscopy and by single-crystal X-ray diffraction. The results show that the hexameric structure is retained upon partial or complete oxidation. <BO>1</BO> was used as aminomethylating agent and reacted with Me<INF>2</INF>AlCl and Me<INF>2</INF>GaCl to give the aminomethylaluminum and -gallium compounds (Me<INF>2</INF>MCH<INF>2</INF>NⁱPr<INF>2</INF>)<INF>2</INF> (M = Al, Ga), which are dimers containing six-membered rings. They were characterized by elemental analyses, NMR spectroscopy, and crystal structure determinations. They are present as dimers containing six-membered M<INF>2</INF>C<INF>2</INF>N<INF>2</INF> rings in solution and in the solid state.