The hydrogen-bonding networks of 2-amino-4-phenyl-1,3-thiazole derivatives

The solid-state packing arrays of nine 4-phenyl substituted 2-amino-1,3-thiazoles have been examined and their hydrogen-bonding networks discussed. The nine compounds, in addition to 2-amino-1,3-thiazole 1, were 2-amino-4-phenyl-1,3-thiazole 2, 2-amino-4-phenyl-1,3-thiazolium bromide monohydrate 3, ethyl 2-amino-4-phenyl-1,3-thiazole-5-carboxylate 4, 2-amino-4-(3-coumarin)-1,3-thiazole 5, 2-amino-4-(4-methylphenyl)-1,3-thiazole 6, 2-amino-4-(2-hydroxyphenyl)-1,3-thiazole 7, 2-amino-4-(4-bisphenyl)-1,3-thiazole 8, 2-amino-4-(1-naphthyl)-1,3-thiazole 9, and 2-amino-4-(2-naphthyl)-1,3-thiazolium bromide 10. The single-crystal x-ray structures of 1–5 have been previously reported while the structures of 6–10 are presented in this paper. A variety of different packing motifs are observed with only four (4, 5, 6 and 9) exhibiting the characteristic R₂²(8) hydrogen-bonded 2-amino-1,3-thiazole dimers. In two of these four structures (6 and 9) potential N–H⋯π hydrogen-bonding interactions exist whereas all remaining structures exhibit a combination of N–H⋯N with either N–H⋯O, N–H⋯S or N–H⋯Br associations in their hydrogen-bonding networks.