两例基于N,N'-双(丙氨酸)萘四甲酰二亚胺的手性镉(Ⅱ)配位聚合物的制备、结构和光致变色性能研究

Preparation,Structure and Photochromic Properties of Two Chiral Cadmium(Ⅱ)Coordination Polymers Based on N,N'-bis-(alanine)naphthalene Diimide

合成了两种手性配体N,N'-双(D-丙氨酸)萘四甲酰二亚胺(N,N'-bis-(D-alanine)naphthalene diimide,D-H_(2)AlaNDI)和N,N'-双(L-丙氨酸)萘四甲酰二亚胺(N,N'-bis-(L-alanine)naphthalene diimide,L-H_(2)AlaNDI).在溶剂热条件下合成了一维链状的配位聚合物[Cd(D-AlaNDI)(4,4'-bipy)_(0.5)(DMF)_(2)]_(n)(1)和[Cd(L-AlaNDI)(4,4'-bipy)_(0.5)(DMF)_(2)]_(n)(2).配位聚合物1为四方晶系,P4_(1)22空间群,一维链通过氢键和范德华力堆积成二维网状结构.配位聚合物1和2为一对对映体,两者均具有光致变色性质,其变色机理是光致电荷转移形成了AlaNDI*自由基阴离子.

Two chiral ligands,N,N'-bis-(D-alanine)naphthalene diimide(D-H_(2) AlaNDI)and N,N'-bis-(L-alanine)naphthalene diimide(L-H_(2) AlaNDI),were synthesized.The one-dimensional chain like coordination polymers[Cd(D-AlaNDI)(4,4'-bipy)_(0.5)(DMF)_(2)]_(n)(1)and[Cd(L-AlaNDI)(4,4'-bipy)_(0.5)(DMF)_(2)]_(n)(2)were synthesized under solvothermal conditions.The crystal of coordination polymer 1 is tetragonal with space group P4_(1)22 and the one-dimensional chains are stacked into two-dimensional network structure through hydrogen bonds and van der Waals forces.Coordination polymers 1 and 2 are one pair of enantiomers with photochromic properties,the mechanism of which is the formation of AlaNDI*radical anion by photo-induced charge transfer.