SYNTHESIS AND THE CHARACTERIZATION OF THE PROTON-TRANSFER COMPOUNDS OF PARA-SUBSTITUTED BENZOIC ACIDS WITH MORPHOLINE

摘要

Ten novel proton-transfer compounds of p-substituted benzoic acids and benzoic acid with .morpholine. have been synthesized. The obtained organic salts were characterized by using infrared and ultraviolet spectroscopy, which confirmed that proton-transfer from the carboxylic acid to morpholine occurred. These data complemented the X-ray crystal structure for I confirming the presence of the COO group on the anion. I crystallized in the monoclinic system, space group P2_1. In crystal the salt units are self-assembled via ionic N-H O strong hydrogen bonds (HB) between the protonated hetero-nitrogen atom of morpholine and the oxygen atoms of carboxylate group of the acid, generating a centrosymmetric antidromic supramolecular synthon, [R4 4~(12) graph set]. These salt units of I serve as building blocks (BB) of the supramolecular architecture chain-like structure joined by C-H...O hydrogen weak bonds forming the 1-D network in the crystal packing.