Diverse Topologies in Chiral Divalent Metal Camphorate Coordination Polymers Containing 4,4′-Dipyridylamine

Abstract

Hydrothermal synthesis has afforded six chiral divalent metal coordination polymers containing d -camphorate ( d -cmph) and 4,4′-dipyridylamine (dpa) ligands, whose topologies depend largely on metal coordination geometry preference. Both cadmium derivatives {[Cd(dpa)( d -cmphH) 2 (H 2 O)]·0.875H 2 O} n ( 1 ) and {[Cd( d -cmph)(dpa)(Hdpa)]ClO 4 } n ( 1a ) exhibit one-dimensional (1-D) chains with protonated pendant ligands; 1 possesses sinusoidal chains with a “wavelength” of over 67 Å. [Zn 2 ( d -cmph) 2 (dpa)(H 2 O)] n ( 2 ) exhibits a two-dimensional (2-D) 3,4-connected binodal net with (5 3 ) 2 (5 4 8 2 ) topology. {[Ni( d -cmph)(dpa)]·3H 2 O} n ( 3 ) and {[M 2 ( d -cmph) 2 (dpa)]·H 2 O} n (M = Co, 4; M = Cu, 5 ) manifest three-dimensional (3-D) networks. The nickel derivative has an uncommon 2-fold interpenetrated 4-connected 4 2 8 4 lvt topology, while the isostructural cobalt and copper complexes possess 6-connected pcu topologies based on {M 2 (OCO) 4 } paddlewheel dimers. Complexes 1/1a and 2 undergo visible light emission upon ultraviolet excitation. Variable temperature magnetic susceptibility experiments indicate weak ( J = −3.6(2) cm –1 ) and strong ( J = –202(5) cm –1 ) antiferromagnetic coupling for 4 and 5, respectively.