2-[(1-{[3-(dimethylazaniumyl)propyl]methylamino}ethylidene)azaniumyl]nonahydro-closo-decaborate dimethyl sulfoxide disolvate

Abstract

The title compound, 2-B10H9NH=C(CH3)N(CH3)CH2CH2CH2N(CH3)2H·2C2H6OS or C8H29B10N3·2C2H6OS, is zwitterionic with the negative charge localized on the decaborate cage and the positive charge on the terminal ammonium group. Two molecules of dimethyl sulfoxide (DMSO) and one molecule of the title compound constitute the asymmetric unit. One DMSO molecule is disordered [ratio 0.739 (3):0.261 (3)]. The bonds and angles within the decaborate cage are within the normal ranges. The amidine fragment of the ligand, which is expected to be planar, is significantly distorted from planarity as exemplified by four torsion angles [B—N—C—C = 8.4 (3), H—N—C—N = 5(2), N—C—N—C = 7.3 (3) and C—C—N—C = 14.8 (3)°] found within this portion of the molecule. The crystal packing consists of head-to-tail-arranged dimers of the title molecule held together by four molecules of DMSO which are attached via strong N—H...O and weak C—H...O hydrogen bonds.