Crystal engineering with heteroboranes. III. 2-Carboxy-1-methoxymethyl-1,2-dicarba-closo-dodecaborane(12)
Abstract
The title compound, 1-CH2OCH3-2-COOH-1,2-closo-C2B10H10 or C5H16B10O3, forms a discrete centrosymmetric tetramer, via hydrogen bonding, involving two inner and two outer carborane molecules. One conventional eight-membered hydrogen-bonded ring [graph set R(8)] is formed between two carboxylic acid groups of the inner carboranes. This interaction is then supplemented by an open finite hydrogen bond (graph set D) between the ether O atom of the inner carborane and the carboxylic acid H atom of the outer carborane.