Lithium Derivatives of Novel Monoanionic Di-N,N‘-chelating Pyridyl- and Quinolyl-1-azaallyl Ligands

The novel lithium complexes [Li{N(SiMe 3 )C(R 2 )C(R 1 )(C 5 H 4 N-2)}] 2 (R 1 = H, R 2 = Bu t ( 1b ); R 1 = SiMe 3, R 2 = Ph ( 1c )) were prepared from the insertion of R 2 CN into [Li{C(SiMe 3 )(R 1 )(C 5 H 4 N-2)}] 2 . Similarly, Li{N(SiMe 3 )C(Ph)C(R)(C 9 H 6 N-2)} (R = H or SiMe 3 ) was prepared from PhCN and Li{C(SiMe 3 )(R)(C 9 H 6 N-2)}. X-ray data are provided for 1b, 1c, and [Li{N(SiMe 3 )C(Ph)C(SiMe 3 )(C 5 H 4 N-2)}(Et 2 O)(PhCN)] ( 1c ‘). Compounds 1b and 1c are dimers in the solid state, whereas 1c ‘ is monomeric.