title: Three substituted (Z)-5-benzylidene-2-thioxothiazolidin-4-ones: hydrogen-bonded dimers that can be effectively isolated or linked into chains either by aromatic pi-pi stacking interactions or by dipolar carbonyl-carbonyl interactions.
abstract: In each of the isomeric compounds (Z)-5-(2-fluorobenzylidene)-2-thioxothiazolidin-4-one, C(10)H(6)FNOS(2), (I), and (Z)-5-(4-fluorobenzylidene)-2-thioxothiazolidin-4-one, C(10)H(6)FNOS(2), (II), there is a very wide C-C-C angle (ca 130 degrees ) at the methine C atom linking the two rings. In each isomer, paired N-H...O hydrogen bonds link the molecules into centrosymmetric R(2)(2)(8) dimers; the hydrogen-bonded dimers are linked into chains by an aromatic pi-pi stacking interaction in isomer (I) and by an antiparallel dipolar carbonyl-carbonyl interaction in isomer (II). (Z)-5-(3,4,5-Trimethoxybenzylidene)-2-thioxothiazolidin-4-one, C(13)H(13)NO(4)S(2), (III), which crystallizes with Z' = 2 in the space group P-1, shows the same very wide angle at the bridging methine C atom; the two independent molecules are linked into an isolated dimer having no crystallographic symmetry.
authors.affiliation: Grupo de Investigación de Compuestos Heterocíclicos, Departamento de Química, Universidad de Valle, AA 25360 Cali, Colombia.
authors.forename: Paula
authors.initials: P
authors.lastname: Delgado
authors.forename: Jairo
authors.initials: J
authors.lastname: Quiroga
authors.forename: Jose M
authors.initials: JM
authors.lastname: de la Torre
authors.forename: Justo
authors.initials: J
authors.lastname: Cobo
authors.forename: John N
authors.initials: JN
authors.lastname: Low
authors.forename: Christopher
authors.initials: C
authors.lastname: Glidewell