SYNTHESIS AND STRUCTURAL SYSTEMATICS OF NITROGEN BASE ADDUCTS OF GROUP-2 SALTS .8. SOME MIXED-LIGAND COMPLEXES OF GROUP-2 METAL-HALIDES WITH AROMATIC N,N'-BIDENTATE AND OXYGEN DONORS

Room-temperature single-crystal X-ray structural characterizations hav e defined an interesting array of species obtained by variously crysta llizing Group 2 halides with 2,2'-bipyridine (bpy) and 1,10-phenanthro line (phen) from hydroxylic solvents. [(phen)(2)Ca(OH2)(3)]Br-2 (1) is monoclinic, P2(1)/c, a 16.896(5), b 8.620(2), c 17.814(5) Angstrom, b eta 97.05(2)degrees, Z = 4 f.u.; conventional R on \F\ was 0.057 for 1 707 independent 'observed' (I > 3 sigma(I)) reflections N-o, the compl ex containing seven-coordinate Ca(N-2)(2)O-3 calcium. [(bpy)(2)CaBr(OH 2)(HOPri)] Br (2) is monoclinic, P2(1)/c, a 9.674(4), b 18.236(8), c 1 4.716(8) Angstrom, beta 90.83(4)degrees, Z = 4 f.u., R 0.044 for N-o 2 349, with seven-coordinate [CaBr(N-2)(2)O-2] calcium. [(bpy)(2)CaBr2(H OPr)] (3), [(bpy)(2)CaBr2(HOBu)] (4) and [(bpy)(2)SrBr2(HOPr)] (5) are all isomorphous, triclinic, <P(1)over bar>, a approximate to 17, b ap proximate to 9.6, c approximate to 7.7 Angstrom, alpha approximate to 105, beta approximate to 94, gamma approximate to 95 degrees, Z = 2 f. u.; R 0.055, 0.037, 0.061 for N-o 3111, 3102, 2424 respectively; all h ave a seven-coordinate [MX(2)(N-2)(2)O] metal environment. A similar a rray is found in [(phen)(2)CaBr(OH2)(HOMe)] Br (6), triclinic, <P(1)ov er bar>, a 16.761(8), b 10.647(6), c 7.376(6) Angstrom, alpha 75.78(6) , beta 82.47(5), gamma 75.86(5)degrees, Z = 2 f.u., R 0.057 for N-o 32 16. With bpy, from aqueous methanol, however, [(bpy)(2)Ca(OH2)(2)(HOMe )(2)]Br-2 (7) was obtained, monoclinic, C2/c, a 17.645(7), b 10.899(4) , c 16.071(5) Angstrom, beta 118.88(2)degrees, Z = 4 f.u., R 0.044 for N-o 1448, containing eight-coordinate Ca(N-2)(2)O-4 calcium; the calc ium is disposed on a twofold axis. [(bpy)(2)SrBr2(HOMe)(2)] (8) is tri clinic, <P(1)over bar>, a 13.784(5), b 10.605(4), c 9.653(1) Angstrom, alpha 115.78(2), beta 96.87(3), gamma 96.67(3)degrees, Z = 2 f.u., R 0.045 for N-o 2754; the strontium is eight-coordinate [SrBr2(N-2)(2)O- 2]. [(phen)(2)Sr(OH2)(4)]I-2.2phen (9), triclinic, <P(1)over bar>, a 1 3.314(4), b 12.311(3), c 7.066(2) Angstrom, alpha 99.77(2), beta 92.43 (2), gamma 77.27(2)degrees, Z = 1 f.u., R 0.049 for N-o 2703, is isomo rphous with the previously studied perchlorate analogue, the strontium being disposed on a centre of symmetry. Species (1)-(9) are all monon uclear; the barium adducts (10) and (11) are binuclear: (mu-OH2)(2)Cl( H2O)(2)Ba(phen)(2)]Cl-2.2phen.4H(2)O (10) is triclinic, <P(1)over bar> , a 14.590(3), b 14.109(4), c 10.862(2) Angstrom, alpha 74.56(2), beta 65.87(2), gamma 63.59(2)degrees, Z = 1 centrosymmetric dimer, R 0.027 for N-o 5249, with nine-coordinate Ba(N-2)(2)ClO2(mu-O)(2) barium. [( bpy)(2)Ba(I/OH2)(mu-I)(3)(I/OH2)Ba(bpy)(2)] (11) is monoclinic, P2/c, a 13.988(2), b 11.00(2), c 20.900(7) Angstrom, beta 127.59(2)degrees, Z = 2 dimers, R 0.069 for N-o 3353, with eight-coordinate Ba(N-2)(2)(I /OH)(mu-I)(3) barium. All of (1)-(11) contain M(N-2)(2) arrays with di verse associations of solvent oxygen atoms, and in some cases halogens . Species (12), [(bpy)BaBr2(HOMe)(2)]((infinity\infinity),) is polymer ic, monoclinic, C2/c, a 17.119(2), b 13.844(1), c 7.489(1) Angstrom, b eta 111.21(1)degrees, Z = 4 f.u., R 0.057 for N-o 2326; the barium lie s on a twofold axis in an eight-coordinate [Ba(N-2)(O)(2)(mu-Br)(4)] e nvironment. An adduct (13) of barium iodide with 4,4'-bipyridine, BaI2 /(4,4'-bpy)/PrOH (1:2 1/2:2), monoclinic, P2(1)/c, a 15.467(5), b 12.6 39(7), c 21.004(5) Angstrom, beta 118.99(3)degrees, Z = 4, R 0.059 for N-o 2.003, is a one-dimensional polymer, linked by two of the 4,4'-bp y ligands, one of these being centrosymmetric; the third ligand occupi es a lattice site, so that the complex is (1/2)Ba(HOPr)(2)]((infinity\ infinity)).(4,4'-bpy). The barium environment is seven-coordinate pent agonal bipyramidal, the two iodines occupying the axial/trans sites an d the two oxygens non-adjacent in the pentagonal plane.