The crystalline α,ω-dicarboxylate metal complex with the longest aliphatic chain to date: uranyl 1,15-pentadecanedioate

Abstract

Under solvo-hydrothermal conditions, 1,15-pentadecanedioic acid (H₂C15) reacts with uranyl ions to form the complex [H₂NMe₂]₂[(UO₂)₂(C15)₃] (1), in which the uranyl ions are tris-chelated by carboxylate groups and the well-ordered aliphatic chains are either all-trans or kinked. 1 crystallizes as a two-dimensional network of the bilayer type and with the {8²·10} point symbol, the packing displaying alternate sheets containing either the ionic parts or stacks of aliphatic chains, at variance with the helicates or honeycomb networks previously obtained with other long-chain HOOC–(CH₂)_n−2–COOH dicarboxylic acids (n = 9–13) and bulkier counterions.