SYNTHESIS AND STRUCTURE OF THE COMPLEXES OF ESTERS OF SOME PHOSPHONIC ACIDS AND AMIDES WITH MOLYBDENUM DIOXODICHLORIDE

ABSTRACT

The complexes LċMoO₂Cl₂ (2), L′·MoO₂Cl₂ (4), L′′·MoO₂Cl₂ (6) and L′′′ċMoO₂Cl₂ (8) were obtained by the reaction of MoO₂Cl₂ and the ligands: L=diethyl ester of 2-dimethylamino-2-oxoethylphosphonic acid (1), L′=diethyl ester of 2-amino-2-oxoethylphosphonic acid (3), L′′=tetraethyl ester of methylenediphosphonic acid (5) and L′′′=tetraethylester of ethylenediphosphonic acid (7). They were characterized by elemental analyses, IR and NMR spectroscopy. The crystal structure of the diphosphonate complex (6) was determined by single crystal X-ray diffraction. The complex was found to crystallize in the monoclinic space group P2₁/n with a=14.999(9) Å, b=7.823(9) Å, c=16.181(10) Å, β=101.962(13)°, V=1857(3) Å³, Z=4, ρ _calcd=1.742(3) mg/m3, R=0.0679, R2w=0.1706, S=1.144 for all 5295 reflections. The structure contains monomeric units of the complex with a sixfold-coordinated Mo atom having a distorted octahedral coordination geometry. The methylenediphosphonate ligand (1) is bonded to the molybdenum atom in a bidentate manner by both P˭O groups.

ACKNOWLEDGMENTS

This work is supported by the Official Cooperation Programs between the Universities of Sofia (Bulgaria) and Hamburg (FRG).