SYNTHESIS AND CHARACTERIZATION OF (BETA-DIKETONATE)(7-TERT-BUTOXYNORBORNADIENE)COPPER(I) COMPOUNDS, A SERIES OF NEW COPPER CVD PRECURSORS

Organocopper compounds of the general formula (beta-diketonate)Cu(7-t-BuO-NBD) where 7-t-BuO-NBD = 7-tert-butoxynorbornadiene and beta-diketonate = 1,1,1,5,5,5-hexafluoro-2,4-pentanedionate (1), 1,1,1-trifluoro-2,4-pentanedionate (2), 2,4-pentanedionate (3), 4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionate (4), 4,4,4-trifluoro-1-phenyl-1,3-butanedionate (5), and 2,2-dimethyl-6,6,7,7,8,8,8-heptafluoro-3,5-octanedionate (6) were prepared by reaction of CuCl with Na(beta-diketonate) in the presence of 7-t-BuO-NBD. All compounds were characterized by elemental analyses and H-1, C-13, and F-19 NMR, IR, and mass spectra. Single-crystal structures of compounds 1; 4, and 5 were determined by X-ray diffraction analyses that showed mononuclear copper species with coordination of a chelating beta-diketonate ligand through two oxygen atoms and the 7-t-BuO-NBD through one C=C double bond and an oxygen atom in the solid state. Variable-temperature H-1 NMR spectral data of compound 2 in the solution are consistent with this structural nature. Hot-wall chemical vapor deposition experiments revealed that compound 1 is suitable as a precursor to deposit copper films in the temperature range 200-260 degrees C. Crystallographic data for compounds 1, 4, and 5: (hfac)Cu(7-t-BuO-NBD) (1) crystallizes in monoclinic system, space group P2(1)/c, a = 8.923(1) Angstrom, b = 19.558(4) Angstrom, c = 10.495(3) Angstrom, beta = 90.45(2)degrees, V = 1831.3(7) Angstrom(3), Z = 4. (Ttfac)Cu(7-t-BuO-NBD) (4) crystallizes in monoclinic system, space group P2(1)/n, a = 10.689(6) Angstrom, b = 9.712(4) Angstrom, c = 19.323(4) Angstrom, beta = 97.22(3)degrees, V = 1990.2(15) Angstrom(3), Z = 4. (Btfac)Cu(7-t-BuO-NBD) (5) crystallizes in triclinic system, space group P (1) over bar, a = 9.617(1) Angstrom, b = 9.894(4)Angstrom, c = 11.322(2) Angstrom, alpha = 104.57(2)degrees, beta = 95.50(1)degrees, gamma = 104.76(3)degrees, V = 993.4(5) Angstrom(3), Z = 2.