Controlling the dimensionality of metal-metal bonded Rh-2(4+) polymers by the length of the linker. A disciplined example of crystal engineering

Reaction of the molecular loop [Rh-2(cis-DAniF)(2)(CH3CN)](2)(malonato)(2), DAniF = N,N'-di-p-anisylformamidinate, with 2 equiv of 2,2',3,3',5,5',6,6' -octafluoro-4,4'-biphenyldinitrile gives a linear tubular structure with Rh -Rh distances of 2.435(1) Angstrom. A comparison of the structures obtained with this molecular loop but employing other linkers support the idea that longer linkers favor one-dimensional structures while shorter linkers favo r two-dimensional structures because of the increased clashing between the large p-anisyl groups. Crystallographic data at 213(2) K for ([Rh-2(cis-DAn iF)(2)](2)(O2CCH2CO2)(2)(NCC6F4C6F4CN)(2)).6.8nCH(2)Cl(2) are: monoclinic, P2(1)/m, a = 11.802(1), b = 28.303(2), c = 18.820(2) Angstrom, beta = 95.67 3(2)degrees, and Z = 2.