title: 2-Methyl-3-(10H-pheno-thia-zin-10-yl)buta-1,3-diene-1,1,4,4-tetra-carbo-nitrile.
abstract: In the title compound, C21H11N5S, the pheno-thia-zine unit has a butterfly structure, and the central six-membered ring adopts a boat conformation. The dihedral angle between the benzene rings is 127.64 (6)°, which is smaller than those reported for similar compounds because of the steric repulsion between the pheno-thia-zine and its tetra-cyano-1,3-butadiene substituent. The di-cyano-vinyl groups are almost orthogonal to one another, making a dihedral angle of 80.58 (6)°. In the crystal, the mol-ecules are aligned along the b axis. Four kinds of weak C-H⋯N inter-actions are recognized, one of which connects the mol-ecules into a one-dimensional array and the remaining three link these arrays.
authors.affiliation: Department of Material Science and Chemistry, Wakayama University, Sakaedani, Wakayama 640-8510, Japan.
authors.forename: Tsunehisa
authors.initials: T
authors.lastname: Okuno
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Iwahashi