The crystal structures of three 3-methyl-1H-1,2,4-triazole-5-thio­nes, including a second polymorph of 4-[(E)-(5-bromo-2-hy­dr­oxy­benzyl­­idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione and a redetermination of 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione

Manjula, P. S. and Sarojini, B. K. and Yathirajan, H. S. and Akkurt, Mehmet and Ersanlı, Cem Cüneyt and Glidewell, Christopher (2015) The crystal structures of three 3-methyl-1H-1,2,4-triazole-5-thio­nes, including a second polymorph of 4-[(E)-(5-bromo-2-hy­dr­oxy­benzyl­­idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione and a redetermination of 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione. Acta Crystallographica Section E, 71 (9). pp. 1003-1009. ISSN 2056-9890

Text (Full Text) The crystal structures of three 3-methyl-1H-1,2,4-triazole-5-thio­nes, including a second polymorph.pdf - Published Version Download (1MB)

Abstract

The structures of three 3-methyl-1H-1,2,4-triazole-5-thione derivatives are reported. The structure of 4-amino-3-methyl-1H-1,2,4-triazole-5(4H)-thione, C3H6N4S, (I), has been redetermined with an improved model for the H atoms: the non-H atoms of (I) all lie on mirror planes in space group Pbcm, and the H atoms of the methyl group are disordered over two sets of reflection-related atomic sites having occupancy 0.5: two independent N—H⋯S hydrogen bonds link the mol­ecules of compound (I) into complex sheets. The non-H atoms in the mol­ecules of 4-[(E)-(3,4-di­meth­oxy­benzyl­idene)amino]-3-methyl-1H-1,2,4-tri­azol-5(4H)-thione, C12H14N4O2S, (II), despite lying in general positions are close to planar, with a dihedral angle between the two rings of 6.31 (10)°: the mol­ecules of compound (II) are linked by a three-centre N—H⋯(O)2 hydrogen bond into a C(10)C(11)[R12(5)] chain of rings. A second polymorph of 4-[(E)-(5-bromo-2-hy­droxy-5-bromo­benzyl­idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione, C10H9BrN4OS, (III), has been identified; the non-H atoms are nearly co-planar with a dihedral angle between the two rings of 1.9 (4)°. There is an intra­molecular O—H⋯N hydrogen bond and the mol­ecules are linked by N—H⋯S hydrogen bonds, forming centrosymmetric R22(8) dimers. Comparisons are made with some related structures.

Item Type:	Article
Uncontrolled Keywords:	crystal structures, 1H-1,2,4-triazole-5-thiones, polymorphism, hydrogen bonding
Subjects:	C Chemical Science > Chemistry
Divisions:	Department of > Chemistry
Depositing User:	C Swapna Library Assistant
Date Deposited:	31 Oct 2019 05:20
Last Modified:	04 Aug 2022 06:07
URI:	http://eprints.uni-mysore.ac.in/id/eprint/9733

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