Four-connected helical chiral coordination polymers based on lactate synthons:Syntheses,structures,and photo-catalytic properties
Enantiomeric lactic derivatives and 3-bromo-4-hydroxybenzoate were used as starting materials to obtain a pair of enantiomers 3-bromo-4-(((1R)-1-carboxyethyl)oxy)benzoic acid(R-H2bba)and 3-bromo-4-(((1S)-1-carboxy-ethyl)oxy)benzoic acid(S-H2bba).As new synthons,R-H2bba and S-H2bba can provide variable coordination modes by two carboxylate groups and chiral source by lactate unit.In the presence of 1,3-di(pyridine-4-yl)propane(1,3-dpp),R-H2bba and S-H2bba further assembled with Ni2+ions under the hydrothermal condition to obtain a pair of chiral coordination polymers(CCPs){[Ni(R-bba)(1,3-dpp)(H2O)0.5]·1.5H2O}n(HU12-R)and {[Ni(S-bba)(1,3-dpp)(H2O)0.5]·1.5H2O}n(HU12-S),respectively.Structural analysis revealed complexes HU12-R and HU12-S are 3D helical frameworks with 4-connected dia net.In complexes HU12-R and HU12-S,R-bba2-and S-bba2-anions are respectively connected by Ni2+centers to form a pair of small enantiomeric helical chains around 2,screw axis.In contrast,1,3-dpp ligands and Ni2+centers construct another pair of large enantiomeric helical chains around 4,or 43 screw axis,respectively.Moreover,the results of electrochemical testing indicated that complex HU12-R is an n-type semiconductor and has a strong absorbing ability for UV-Vis light and low resistance in charge transporta-tion.By comparing with R-H2bba,1,3-dpp,and Ni2+ions,HU12-R indicates obvious catalytic activity in the degra-dation of dyes under ultraviolet light.CCDC:2280879,HU12-R;2280880,HU12-S.
万方数据
维普
