Open-Framework Copper Adeninate Compounds with Three-Dimensional Microchannels Tailored by Aliphatic Monocarboxylic Acids

A series of isostructural copper(II) coordination polymers containing the nucleobase adenine and different monocarboxylic acids as bridging ligands, [Cu2(μ3-ade)2(μ2-OOC(CH2)nCH3)2]·xH2O (n from 0 to 5), have been prepared. Single-crystal X-ray analysis of acetate (n = 0) and butanoate (n = 2) compounds shows a covalent three-dimensional network in which the copper(II) centers are bridged by μ-N3,N7,N9-adeninato and μ-O,O′-carboxylato ligands, with crystallization water molecules trapped in the pores, which are decorated by the Watson–Crick faces of the adenine. The tunable permanent porosity of guest-free compounds was confirmed by gas adsorption measurements.