Crystallographic characterization of the first reported crystalline form of the potent hallucinogen (<i>R</i>)-2-amino-1-(8-bromobenzo[1,2-<i>b</i>;5,4-<i>b</i>′]difuran-4-yl)propane or `bromodragonfly': the 1:1 anhydrous proton-transfer compound with 3,5-dinitrosalicylic acid
作者:Graham Smith、Marcus S. Cotton、Urs D. Wermuth、Sue E. Boyd
DOI:10.1107/s0108270110012850
日期:2010.5.15
The 1: 1 proton-transfer compound of the potent substituted amphetamine hallucinogen (R)-2-amino-1-(8-bromobenzo[1,2-b;5,4-b']difuran-4-yl)propane (common trivial name 'bromodragonfly') with 3,5-dinitrosalicylic acid, namely 1-(8-bromobenzo[1,2-b;5,4-b']difuran-4-yl)propan-2-aminium 2-carboxy-4,6-dinitrophenolate, C13H13BrNO2+center dot C7H3N2O7-, forms hydrogen-bonded cation-anion chain substructures comprising undulating head-to-tail anion chains formed through C(8) carboxyl-nitro O-H center dot center dot center dot O associations and incorporating the aminium groups of the cations. The intrachain cation-anion hydrogen-bonding associations feature proximal cyclic R-3(3)(8) interactions involving both an N+-H center dot center dot center dot O-phenolate and the carboxyl-nitro O-H center dot center dot center dot O associations and aromatic pi-pi ring interactions [minimum ring centroid separation = 3.566 (2) angstrom]. A lateral hydrogen-bonding interaction between the third aminium H atom and a carboxyl O-atom acceptor links the chain substructures, giving a two-dimensional sheet structure. This determination represents the first of any form of this compound and is in the (R) absolute configuration. The atypical crystal stability is attributed both to the hydrogen-bonded chain substructures provided by the anions, which accommodate the aminium proton-donor groups of the cations and give crosslinking, and to the presence of the cation-anion aromatic ring pi-pi interactions.