Role of ligand conformation in the structural diversity of divalent complexes containing phosphinic amide ligand

摘要

Reactions of the phosphinic amide ligand N-(4-methyI-2-pyrimidinyl)-P,P-diphenyl-phosphinic amide, L, with the corresponding metal salts afforded the complexes [Zn(L)Cl2]_∞, 1, and Co3(L)4Br6, 2, which have been structurally characterized by X-ray crystallography. The molecules of the free L ligands are interlinked through N-H-N and C-H-O hydrogen bonds to form a linear chain, whereas complex 1 shows the 1D helical chain structure, which is the first coordination polymer containing phosphinic amide ligands, and 2 is a linear Co(II) trimer with a rare mixed T_d-O_h-T_d geometry. While the free L ligand adopts the aligned conformation, those in 1 and 2 adopts the cis and both the cis and trans conformations, respectively.