SYNTHESIS AND STRUCTURE OF TETRAPHENYLANTIMONY HYDROGEN PHTHALATE

Tetraphenylantimony hydrogen phthalate, Ph(4)SbOC(O)C6H4COOH-o, was pr epared by the reaction of pentaphenylantimony with phthalic acid. Acco rding to the data of X-ray structural analysis, the resulting compound is a trigonal-bipyramidal complex of antimony with three phenyl group s in equatorial positions; the fourth phenyl group and the carboxyl fr agment are in axial positions. The CSbO angle is 177.5(1)degrees; the Sb-C(Ph)(eq) and Sb-C(Ph)(ax) distances are 2.099(4)-2.177(4) Angstrom and 2.129(4) Angstrom, respectively. The H atom of the free carboxyl group and the carbonyl O atom of another carboxylate group form an int ramolecular hydrogen bond.