142797-61-3Relevant academic research and scientific papers
Organometallic polymer and linear mono-, bi-, and trimetallic octafluoro-p,p′-biphenylene-bridged complexes of bis(methyldiphenylphosphine)nickel: X-ray crystal structures of Ni(PMePh2)2(4,4′-C12F8H)Br and Ni(PMePh2)2(4,4′-C12F8H) 2
Sturge, K. Craig,Hunter, Allen D.,McDonald, Robert,Santarsiero, Bernard D.
, p. 3056 - 3062 (2008/10/08)
Metathesis reactions between organolithium reagents and nickel bromide complexes are used to prepare a series of five linear mono-, bi- and trimetallic oligomers of Ni(PMePh2)2 having the octafluoro-p,p′-biphenylene bridging unit (i.e. Ni(PMePh2)2(4,4′-C12F8H)Br, Ni(PMePh2)2(4,4′-C12F8H) 2, [Ni(PMePh2)2]2(μ-4,4′-C 12F8)Br2, [Ni(PMePh2)2]2(μ-4,4′-C 12F8)(4,4′-C12F8H) 2, and [Ni(PMePh2)2]3(μ-4,4′-C 12F8)2Br2). These complexes have been characterized by conventional analytical and spectroscopic means, and two representative examples have had their structures confirmed by X-ray crystallography: Ni(PMePh2)2(4,4′-C12F8H)Br (C38H27BrF8NiP2; a = 15.952 (5), A?, b = 17.080 (4), A?, c = 14.048 (4), A?, β = 116.42 (3)°, V = 3427 A?3; monoclinic; C2/c, Z = 4) and Ni(PMePh2)2(4,4′-C12F8H) 2 (C50H28F16NiP2; a = 10.718 (11) A?, b = 16.424 (7), A?, c = 13.202 (6), A?, β = 110.41 (6)°, V = 2178.1 A?3; monoclinic; P21/c, Z = 2). The 1H, 19F, and 31P NMR data for these complexes suggest that, in contrast to the analogous tetrafluoro-p-phenylene-bridged species, there is no significant electronic interaction between adjacent metal centers in the octafluoro-p,p′-biphenylene-bridged complexes. This suggestion is consistent with the large twist angles (52.2 and 53.1°) observed between rings of the octafluorobiphenyl groups. The related reaction between 4,4′-C12F8Li2 and Ni(PMePh2)2Br2 produces the first example of an arene-bridged organometallic polymer (i.e. -[Ni(PMePh2)2(μ-4,4′-C12F 8)]n-). Its spectroscopic properties suggest that its repeating units have the same structures (i.e. 4,4′-disubstituted C12F8 bridging units and para-substituted Ni(PMePh2)2(aryl)2 fragments) as do the discrete oligomers.
