Authors: De Souza, M.V.N.; Gonçalves, R.S.B.; Wardell, S.M.S.V.; Wardell, J.L.
AbstractThe crystal structures of three isomeric 4-[3-(dichlorophenyl)-hexahydro[1,3]oxazolo[3,4-a]pyridin-1-yl]-2,8-bis(trifluoromethyl)quinolines, (5: X2 = 2,3-, 2,4- and 2,5-Cl2) have been determined and have been compared to those of related compounds. The crystallographic asymmetric unit of each of (5: X2 = 2,4-Cl2) and (5: X2 = 3,4-Cl2) consists of a single molecule, while that of (5: X2 = 2,3-Cl2) contains two independent molecules – Molecule A and Molecule B. Each of the three compounds crystallizes in the triclinic space group, P1̅. The supramoleular arrangements of the three compounds are generated from combinations of some of C–H⋯X (X = F, Cl, and O), C–X⋯π (X = H, F and Cl) and π⋯π interactions. The presence and significance of two centrosymmetric structural dimeric motives – cage-type dimers, formed (i) from the intermeshing of “F”-shaped monomers, and (ii) π(quinoline)⋯π(quinoline) interactions, reported to arise frequently in other 4-[3-aryl-hexahydro[1,3]oxazolo[3,4-a]pyridin-1-yl]-2,8-bis(trifluoromethyl)quinolone compounds, were investigated. Both (5: X2 = 2,4-Cl2) and (5: X2 = 3,4-Cl2) exhibit cage-type dimers. In the cases of molecule B of (5: X2 = 2,3-Cl2) and (5: X2 = 3,4-Cl2), the π(quinoline)⋯π(quinoline) interactions are strong, but are much weaker in molecule A of (5: X2 = 2,3-Cl2) and (5: X2 = 2,4-Cl2).
Keywords: π⋯π interactions: C–H⋯X (X = halo) interactions; C–X⋯π (X = halo) interactions; mefloquine derivatives; quinoline derivatives; X-ray crystallographyDocument Type: Research ArticleDOI: 10.1515/zkri-2014-1789Publication date: 1 de Abril de 2015