Synthesis and characterization of volatile mixed-metal yttrium-barium, barium-copper and yttrium-copper beta-diketonatofluoroisopropoxides. Molecular structure of BaY2[mu-OCH(CF3)(2)](4)(thd)4

Heterometallic complexes [YBa2(HFIP)(7)(THF)(3)] (1) and [BaCu(HFIP)(4)(DME)(2)] (2); HFIP = 1,1,1,3,3,3-hexafluoro-2-propoxide) were obtained by metathesis reactions between YCl3 or CuCl2 and ''Ba(HFIP)(2)'' obtained in situ or by using the isolated barium hexafluoroisopropoxide [Ba-5(OH)(HFIP)(9)(THF)(4)(H2O)]. The fluoroisopropoxides [Y(HFIP)(3)(THF)(3)] (3) and [Y-2(HFIP)(2)(thd)(4)] (4) are alternative yttrium sources. Volatile mixed-metal complexes [Y2Ba(HFIP)(4)(thd)(4)] (5), [BaCu2(HFIP)(4)(thd)(2)] (6) and [YCu (HFIP)(thd)] (7); thdH = 2,2,6,6-tetramethyl-3,5-heptanedione) were synthesized by reacting 1, 2 or 3 with tetramethylheptanedionates of yttrium, copper and barium or directly with Hthd for 5 and 6. An alternative route to 5 was the reaction of 4 with [Ba-5(OH)(HFIP)(9)(THF)(4)(H2O)]. The compounds were all obtained in high yields. They were characterized by elemental analysis, mass spectrometry, NMR (H-1, F-19, C-13 {H-1}) and ESR spectroscopy, as well as vapour pressure measurements and single-crystal X-ray diffraction for 5. The volatilities of compounds 5, 6 and 7 are in the range 150-170 degrees C/10(-3) Torr and are the best encountered among mixed-metal compounds containing barium, yttrium and copper. Copyright (C) 1996 Elsevier Science Ltd