The crystal structures of salts of N -(4-fluoro-phen-yl)piperazine with four aromatic carb-oxy-lic acids and with picric acid

• Published in: Acta crystallographica. Section E, Crystallographic communications Vol. 76; no. Pt 8; pp. 1179 - 1186
• Main Authors: Harish Chinthal, Chayanna, Yathirajan, Hemmige S, Kavitha, Channappa N, Foro, Sabine, Glidewell, Christopher
• Format: Journal Article
• Language: English
• Published: England International Union of Crystallography 01.08.2020
• Subjects: Research Communications; mol­ecular structure; crystal structure; hydrogen bonding; piperazines; piperazine salts; supra­molecular assembly
• ISSN: 2056-9890; 2056-9890
• DOI: 10.1107/S2056989020008749

The structures are reported for five salts formed by reactions between -(4-fluoro-phen-yl)piperazine and aromatic acids. In 4-(4-fluoro-phen-yl)piperazin-1-ium 2-fluoro-benzoate monohydrate, C H FN ·C H FO ·H O, (I), the components are linked by a combination of N-H⋯O and O-H⋯O hydrogen bonds to form a chain of alternating (12) and (16) rings. The ionic components of 4-(4-fluoro-phen-yl)piperazin-1-ium 2-bromo-benzoate 0.353-hydrate, C H FN ·C H BrO ·0.353H O, (II), are linked by N-H⋯O hydrogen bonds to form a centrosymmetric four-ion aggregate containing an (12) motif, and these aggregates are linked into a mol-ecular ladder by a single C-H⋯π(arene) hydrogen bond. 4-(4-Fluoro-phen-yl)piperazin-1-ium 2-iodo-benzoate, C H FN ·C H IO , (III), crystallizes with ' = 2 in space group : the four independent ions are linked by N-H⋯O hydrogen bonds to form a non-centrosymmetric aggregate again containing an (12) motif, and aggregates of this type are linked into a ribbon by a combination of C-H⋯O and C-H⋯π(arene) hydrogen bonds. The anion in 4-(4-fluoro-phen-yl)piperazin-1-ium 2,4,6-tri-nitro-phenolate, C H FN ·C H N O , (IV), shows clear evidence of extensive electronic delocalization from the phenolate O atom into the adjacent ring. The ions are linked by a combination of two-centre N-H⋯O and three-centre N-H⋯(O) hydrogen bonds to form centrosymmetric four-ion aggregates containing three types of ring. The ions in 4-(4-fluoro-phen-yl)piperazin-1-ium 3,5-di-nitro-benzoate, C H FN ·C H N O , (V), are again linked by N-H⋯O hydrogen bonds to form centrosymmetric (12) aggregates, which are themselves linked by a C-H⋯π(arene) hydrogen bond to form sheets, the stacking of which leads to the formation of narrow channels, containing disordered and/or mobile solvent entities. Comparisons are made with some related structures.