Silver(I) coordination polymers of the ‘hinged’ pyrazine containing ligand di-2-pyrazinylmethane

Abstract

Herein, we report a series of 1D, 2D and 3D coordination polymers formed from di-2-pyrazinylmethane (dpzm) and silver(I) salts in which we examine the role the non-coordinating methylene hinge plays in distorting these structures away from those observed for related pyrazine containing coordination polymers. {[Ag2(dpzm)(NO3)2]}n (1) is a 1D ladder-like structure, {[Ag(dpzm)]SO3CF3}n (2) is a 44 connected 2D network and {[Ag2(dpzm)3](X)2}n (X = ClO4, 4a; X = PF6, 4b), {[Ag4(dpzm)5](BF4)4}n (5) and {[Ag3(dpzm)4](SbF6)3}n (6) have pseudo-cubic lattices with some connections between Ag(I) centres missing; this is a consequence of the pyrazine in some cases only acting as a monodentate group (4) or a low ligand:Ag ratio in 5 and 6. Most of the structures compare well to previously reported 1D, 2D and 3D assemblies formed with pyrazine, although an evident feature of dpzm coordination was the geometrical restriction of the methylene hinge, which was apparent in the long Ag–N bond lengths observed for the 3D materials.