Supramolecular Squarate and Hydrogensquarate Compounds with 4-Amino 2-Aminothiazole and 2-Aminobenzimidazole

Abstract

Three organic amine squarate salts were synthesized and characterized by means of elemental analysis, FT-IR spectroscopy and thermal analysis (TG, DTG and DTA). The crystal structures of 4-amino-4H-1,2,4-triazolium hydrogenesquarate, (C<inf>2</inf>H<inf>5</inf>N<inf>4</inf>)(HC<inf>4</inf>O<inf>4</inf>) (I), bis(2-aminothiazolium) squarate dihydrate, (C<inf>3</inf>H<inf>5</inf>N<inf>2</inf>S)<inf>2</inf>(C<inf>4</inf>O<inf>4</inf>)·2H<inf>2</inf>O (II) and bis(2-amino-1H-benzo[d]imidazolium) squarate, (C<inf>7</inf>H<inf>8</inf>N<inf>3</inf>)<inf>2</inf>(C<inf>4</inf>O<inf>4</inf>) (III) have also been studied. They crystallizes in the monoclinic system, space group P2<inf>1</inf>/c, C2/c and C2/c, respectively. The organic amine molecules link the squarate ions via N-H⋯O hydrogen bonds. All the organic amine squarates show similar decomposition behaviour and decomposed in two or three thermal stages. © 2007 Elsevier B.V. All rights reserved.