Magnesium iodide-4,4'-bipyridine-water (1/3/4) and strontium iodide-4,4'-bipyridine-propan-1-ol (1/2.5/2).

Both of the title compounds, catena-poly[[[tetraaqua-magnesium(I)]-μ-4,4'-bipyridine-κ 2 N:N'] diiodide bis(4,4'-bi-pyridine) solvate], ([Mg(C 10 H 8 N 2 )(H 2 O) 4 )I 2 .2C 10 H 8 N 2 } n , (I), and catena-poly[[[μ-4,4'-bipyridine-bis[diiodobis(propan-1-ol)strontium(I)]]-di-μ-4,4'-bipyridine-κ 4 N:N'] bis(4,4'-bipyridine) solvate], ([Sr 2 I 4 (C 10 H 8 N 2 ) 3 (C 3 H 8 O) 4 ].2C 10 H 8 N 2 } n , (II), are one-dimensional polymers which are single- and doublestranded, respectively, the metal atoms being linked by the 4,4'-bipyridine moieties. The Mg complex, (I), is [cis-((H 2 O) 4 Mg(N-4,4'-bipyridine-N') (2/2) }] ( ∞ | ∞)1 2 .4,4'-bipyridine and Mg has a six-coordinate quasi-octahedral coordination environment. The Sr complex, (II), is isomorphous with its previously defined Ba counterpart [Kepert, Waters & White (1996). Aust. J. Chem. 49, 117-135], being [(propan-1-ol) 2 - I 2 Sr(N-4,4'-bipyridine-N') (3/2) ] ( ∞ | ∞ ) .4,4'-bipyridine, with the I atoms trans-axial in a seven-coordinate pentagonal-bipyramidal Sr environment.