Synthesis and Structural Systematics of Nitrogen Base Adducts of Group 2 Salts. X. Some Mixed-Ligand Complexes of Group 2 Metal Halides With 2,2':6',2"-Terpyridine and Oxygen Donors

Abstract

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] Br4.PriOH (1) is triclinic, Pi, a 19.352(6), b 12.852(5), c 11.463(3) ?, a 110.95(3), ß 99.04(2), ? 98.81(3)°, Z = 2 f.u .; conventional R on ? F ? at convergence was 0.056 for No 4398 independent 'observed' (I > 3s(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) ?, while in [Mg( tpy )(OH2)3]2+, Mg-N(central; distal) are 2.139(7); 2.206(9), 2.222(9) ?, while Mg-O trans to these are 2.042(6); 2.082(9), 2.097(8) ?. [Mg( tpy )(OH2)2( MeOH )] Cl2 (2) is triclinic, Pi, a 14.049(7), b 8.354(4), c 8.301(2) ?, a 74.25(3), ß 73.05(3), ? 80.37(4)°, Z = 2 f.u., R 0.064 for No 2417. In the cation, Mg-N(central; distal) are 2.125(4); 2.203(4), 2.218(4) ?; Mg-O( MeOH ) is trans to Mg-N(central), being 2.013(4) ?; Mg-O(OH2) are 2.067(4) and 2.063(4) ?. [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) ?, ß 109.56(5)°, Z = 4 centrosymmetric dimers, R 0.061 for No 985. The calcium atoms are linked by a pair of µ-chlorines, CaCl2Ca, and are seven-coordinate, N3Ca(µ-Cl )4 being broadly coplanar in the equatorial plane of a pentagonal bipyramidal array, with the other chlorine and the dmf oxygen trans and axial.