Novel Zn(II) coordination polymers based on the natural molecule bisdemethoxycurcumin

Abstract

This article introduces a new family of coordination polymers (CPs) that contains a renewable curcumin derivative, the bisdemethoxycurcumin (BDMC), coordinated to Zn(II) centers. The reaction between BDMC and zinc acetate, performed under mild conditions in ethanol, provides a new 1D phase termed BDMCZn-1. In addition, dimensionality and porosity of this network have been expanded by studying the reaction occurring between three species, the BDMC, the Zn(II), and a ditopic colinker: 1,2-bis(4-pyridyl)ethylene, 1,3-bis(4-pyridyl)propane, or 4,4′-bipyridine. In total, seven new CPs are presented, named BDMCZn-x. The structures of five of them were elucidated by single-crystal X-ray diffraction. Moreover, we show that the combination of the latest technique with solid-state 13C nuclear magnetic resonance is a powerful tool set to analyze the coordination modes of the BDMC, providing insight into the two unresolved structures. In the achievement of the new CPs, we further discuss the coordination capacity of BDMC, the relevance of solvents, and supramolecular interactions.