Crystal structures of the cis and trans isomers of a tetrathia[3.3.3.3]cyclophane

Abstract

Both the cis and trans isomers of 3,11,18,26-tetrathiatricyclo[26.2.2.15,9.213,16.120,24] hexatriaconta-5,7,9,20,22,24-hexene have been prepared and structurally characterized. Each of these centrosymmetric tetrathia dimers includes two cyclohexane rings in chair conformations with either 1,4-cis or 1,4-trans bonding and two meta-substituted benzene rings. The cis isomer packs into the monoclinic space group P21/a with a = 10.485(3)A, b = 10.3956(18)A, c = 14.1343(10)A, β = 105.200(13)°, Z = 2 and refined to an R factor of 0.046. The trans isomer crystallizes in the monoclinic space group P21/c with a = 10.7217(12)A, b = 5.6797(7)A, c = 25.415(5)A, β = 96.001(12)°, Z = 2 and refined to an R factor of 0.043. In the cis structure each benzene ring faces a cyclohexane ring while in the trans structure the cyclohexane rings face one another.