Cocrystallization of N-donor type compounds with 5-sulfosalicylic acid：The effect of hydrogen-bonding supramolecular architectures

Benzotriazole,N,N＇-dimethylpiperazine and N-methylpiperazine were applied to crystallize with 5-sulfosalicylic acid（5-H2SSA）,affording three new binary molecular cocrystals [（C6H6N3＋）.（C7H5O6S-）].H2O（1）,[（C6H16N22＋）1/2.（C7H5O6S-）].H2O（2） and [（C5H14N22＋）.（C7H5O6S-）2].3H2O（3） under general conditions.Proton-transferring occurs from acid to nitrogen of N-donor compounds in all compounds 1,2 and 3.Analysis of the hydrogen-bonding synthons and their effects on crystal packing were also presented in the context of crystal engineering and host-guest chemistry.In compound 1,1-D infinite chains are extended to a 2-D layered architecture via strong O-H...O hydrogen bonds and then to a 3-D network by N-H...O interactions.Compound 2 and 3 both have the 1-D chain which is formed by O-H...O bonds and weak C-H...O hydrogen bonds.A common intramolecular S（6） [synthon I] ring is formed by the hydroxyl with the carboxyl group in all three compounds.