A NEW BIMETALLIC BARIUM YTTRIUM OXO ALKOXIDE MU(3)-OET)(6)(MU(3)-OH)(2)(DPM)(6)CENTER-DOT-2ETOH - STRUCTURAL CHARACTERIZATION AND THERMAL-BEHAVIOR

Ba2Y4(mu(6)-O)(mu(3)-OEt)(6)(mu(3)-OH)(2)(dpm)(6) . 2EtOH (2) (dpm = 2 ,2,6,6-tetramethylheptane-3,5-dionato) was prepared from alkoxides of the two metals in the presence of 2,2,6,6-tetramethylheptane-3,5-dione . This compound was characterized by elemental analysis, H-1 NMR spect roscopy, mass spectrometry and an X-ray crystal study. Complex 2 cryst allizes in the monoclinic space group P2(1)/c with unit cell parameter s a = 14.512(5), b = 22.202(6), c = 18.461(4) Angstrom, beta = 112.87( 2)degrees, V = 5480.4 Angstrom(3), Z = 2 and R = 0.0773 for 1403 obser ved reflections. Its crystal structure consists of a Ba2Y4 octahedron encapsulating a mu(6)-O unit. Six faces of the octahedron are capped b y mu(3)-OEt ligands whereas the two others are capped by mu(3)-OH liga nds. Each metal atom is chelated by a terminal dpm ligand. Yttrium ato ms are heptacoordinated while barium atoms are octacoordinated with on e terminal EtOH ligand. Its thermal behavior was studied by TG analysi s. The data were compared with the results already obtained for the st ructurally similar complex Ba2Y4(mu(6)-O)(mu(3)-OEt)(8)(dpm)(6) (1).