Structures of the reaction products of lithium metal with N , N -dimethylacetamide and tetramethylurea

The reaction of lithium metal with dry N , N -dimethylacetamide produced crystals of catena -poly[(μ 3 - N , N -dimethylacetoacetamidato)lithium(I)], [Li(C 6 H 10 NO 2 )] n , ( I ), which crystallizes as a coordination polymer with a chain of fused Li 2 O 2 rings. A similar reaction of lithium metal with N , N -tetramethylurea produces crystals of hexakis[μ 3 -1,2-bis(dimethylamino)-2-oxoethan-1-olato]hexalithium(I), [Li 6 (C 6 H 13 N 2 O 2 ) 6 ], ( II ), which crystallizes as a hexamer, with the alkoxide O atoms in a Li 6 O 6 barrel-shaped cluster with threefold symmetry, and the keto O atoms bonded to the lithium atoms outside the cage.