Tyrammonium 4-nitrophthalate dihydrate: structural and spectroscopic elucidation

Tyrammonium 4-nitrophthalate has been synthesized and its structural and spectroscopic properties elucidated by single-crystal X-ray diffraction, solid-state polarized IR-spectroscopy of oriented colloids in a nematic host, HPLC with tandem mass spectrometry (HPLC ESI-MSMS), and TGV and DSC methods. The compound crystallizes in the monoclinic P21/c space group and its structure consists of a 3D network of molecules joined by intermolecular interactions with the participation of cations, anions and two solvent molecules. The tyrammonium cation adopts a T trans configuration with corresponding angles of ϕ 1 = 76.0(4)°, ϕ 2 = 54.8(1)° and ϕ 3 = 63.4(1)°, respectively. In the 4-nitrophthalate anion, the COO− and COOH groups are turned off the plane of the benzene ring at angles of τ 1 = 88.1(5)° and τ 2= 22.1(7)°, respectively.