Crystal and Molecular Structure of Four Organic Salts from Benzylamine and Carboxylic Acids

Abstract

Four salts benzylammonium (4-chloro-phenoxy)-acetate monhydrate (1), benzylammonium 3,5-dinitrosalicylate (2), benzylammonium 2,5-bis-benzylcarbamoyl-terephthalate (3), and benzylammonium 4-nitro-phthalate monohydrate (4) were obtained from self-assembly of the corresponding carboxylic acids with the benzylamine, and their structures were fully characterized. All four compounds are ionic, with proton transfer occurring to the NH2 of the benzylamine moiety. Compound 1 crystallizes in the Monoclinic, space group P2(1)/n, with a = 6.7577(5) A, b = 8.3490(7) A, c = 28.658(2) A, β = 95.765(2)°, V = 1608.7(2) A3, Z = 4. Compound 2 crystallizes in the Triclinic, space group P-1, with a = 9.7082(11) A, b = 10.9970(11) A, c = 15.9915(17) A, α = 98.2230(10)°, β = 102.6500(10)°, γ = 114.105(2)°, V = 1467.9(3) A3, Z = 4. Compound 3 crystallizes in the Monoclinic, space group P2(1)/c, with a = 15.8100(12) A, b = 5.6638(3) A, c = 20.1245(17) A, β = 106.857(2)°, V = 1724.6(2) A3, Z = 2. Compound 4 crystallizes in the Monoclinic, space group Pc, with a = 17.3360(19) A, b = 9.4133(8) A, c = 14.5066(16) A, β = 112.104(2)°, V = 2193.3(4) A3, Z = 4. Supramolecular architectures of the compounds 1–4 involve O–H···O/N–H···O/N–H···N hydrogen bonds as well as other non-covalent associations. These salts displayed 2D–3D framework structures for the synergistic effect of the various non-covalent interactions. The crystal structures of the benzylamine salts with (4-chloro-phenoxy)-acetic acid, 3,5-dinitrosalicylic acid, 2,5-bis-benzylcarbamoyl-terephthalic acid, and 4-nitro-phthalic acid show extensive hydrogen bonding as well as other noncovalent interactions, linking discrete components into higher-dimensional networks.