Synthesis, crystal structure, and non-covalent interactions in 4-hydrazinobenzoic acid hydrochloride

The compound 4-hydrazinobenzoic acid hydrochloride (4-HBA), C7H9O2·Cl, has been synthesized and characterized by FT-IR spectroscopy and X-ray diffraction. The compound crystallizes as colourless needles in a triclinic system, space group Pˉ1 (Z = 2), and cell parameters a = 3.7176 (4) Å, b = 5.9133 (4) Å, c = 19.3631 (13) Å, α = 87.841 (6), β = 88.924 (6), γ = 80.203 (6), V = 419.13 (6) Å3. The component ions are linked by a combination of O–H⋯O, N–H⋯N and N–H⋯Cl hydrogen bonds to form a complex three-dimensional framework structure in which each cation is linked to two other cations, by O–H⋯O and N–H⋯N hydrogen bonds, and to five different anions, while each anion accepts hydrogen bonds from five different cations. Calculations on the Non-Covalent Interactions (NCI) amplify the crystallographic conclusions concerning the interionic hydrogen bonds. [Display omitted] •The synthesized compound is an intermediate for the synthesis of new compounds with pharmacological interest.•There is little evidence in the literature on this type of derivatives and the first report is more than 50 years old.•Crystallographic data reveal that 4-HBA form a complex three-dimensional framework structure between cations and anions.•Crystallographic observations were confirmed through the results obtained with the non-covalent interactions calculations.