SYNTHESIS AND STRUCTURAL SYSTEMATICS OF NITROGEN BASE ADDUCTS OF GROUP-2 SALTS .10. SOME MIXED-LIGAND COMPLEXES OF GROUP-2 METAL-HALIDES WITH 2,2' 6',2''-TERPYRIDINE AND OXYGEN DONORS/

Room-temperature single-crystal X-ray structural characterizations are recorded for a variety of adducts of Group 2 metal halides with 2,2': 6',2 ''-terpyridine (tpy) from various hydroxylic solvents. [Mg(tpy)(2 )] [Mg(tpy)(OH2)(3)] Br-4.(PrOH)-O-i (1) is triclinic, <P(1)over bar>, a 19.352(6), b 12.852(5), c 11.463(3) Angstrom, alpha 110.95(3), beta 99.04(2), gamma 98.81(3)degrees, Z = 2 f.u.; conventional R on /F/ at convergence was 0.056 for N-o 4398 independent 'observed' (I > 3 sigm a(I)) reflections. In the [Mg(tpy)(2)](2+) ion, Mg-N(central; distal) are 2.099(9), 2.09(1); 2.152(9)-2.212(8) Angstrom, while in [Mg(tpy)(O H2)(3)](2+), Mg-N(central; distal) are 2.139(7); 2.206(9), 2.222(9) An gstrom, while Mg-O trans to these are 2.042(6); 2.082(9), 2.097(8) Ang strom. [Mg(tpy)(OH2)(2) (MeOH)] Cl-2 (2) is triclinic, <P(1)over bar>, a 14.049(7), b 8.354(4), c 8.301(2) Angstrom, alpha 74.25(3), beta 73 .05(3), gamma 80.37(4)degrees, Z = 2 f.u., R 0.064 for N-o 2417. In th e cation, Mg-N(central; distal) are 2.125(4); 2.203(4), 2.218(4) Angst rom; Mg-O(MeOH) is trans to Mg-N(central), being 2.013(4) Angstrom; Mg -O(OH2) are 2.067(4) and 2.063(4) Angstrom. [CaCl2(tpy)(dmf)](2) (3) ( dmf = N,N-dimethylformamide) is monoclinic, C2/c, a 23.27(2), b 11.225 (6), c 16.517(8) Angstrom, beta 109.56(5)degrees, Z = 4 centrosymmetri c dimers, R 0.061 for N-o 985. The calcium atoms are linked by a pair of mu-chlorines, CaCl2Ca, and are seven-coordinate, N3Ca(mu-Cl)(4) bei ng broadly coplanar in the equatorial plane of a pentagonal bipyramida l array, with the other chlorine and the dmf oxygen trans and axial.