Reactions of CO(2) and CS(2) with 1,2-bis(di-tert-butylphosphino)ethane complexes of nickel(0) and nickel(I).
Reaction of CS(2) with [(dtbpe)Ni](2)(η(2),μ-C(6)H(6)) (1; dtbpe =1,2-bis(di-tert-butylphosphino)ethane) in toluene gives the carbon disulfide complex (dtbpe)Ni(η(2)-CS(2)) (2), characterized by standard spectroscopic methods and X-ray crystallography. Reaction of CS(2) with the Ni(I) complex (dtbpe)Ni(OSO(2)CF(3)) gives the diamagnetic, trimetallic cluster [{(dtbpe)Ni(κ(1),η(2)-CS(2))}(2)(dtbpe)Ni][SO(3)CF(3)](2) (3-OTf). The solid-state structure of 3-OTf reveals that the two CS(2) ligands bind η(2) to two (dtbpe)Ni centers and κ(1) to the third, unique (dtbpe)Ni in the complex dication, and NMR spectroscopic data indicate that this structure is maintained in solution. Oxidation of 2 by ferrocenium hexafluorophosphate affords the identical trimetallic complex dication as the PF(6)(-) salt, [{(dtbpe)Ni(κ(1),η(2)-CS(2))}(2)(dtbpe)Ni][PF(6)](2) (3-PF(6)). These results are consistent with the intermediacy of a Ni(I)-CS(2) complex, [(dtbpe)Ni(CS(2))(+)], that is unstable with respect to disproportionation. Reaction of 1 with one equivalent of CO(2) provides the carbon dioxide adduct (dtbpe)Ni(η(2)-CO(2)) (4), that was also crystallographically characterized. Thermolysis of 4 in benzene solution at 80 °C results in reduction of the CO(2) ligand to CO, trapped as (dtbpe)Ni(CO)(2), and partial oxidation of a dtbpe ligand to give O═P(tert-Bu)(2)CH(2)CH(2)P(tert-Bu)(2).
Anderson
John S
JS
Department of Chemistry, Gordon Center for Integrative Science, The University of Chicago, 929 E. 57th Street, Chicago, Illinois 60637, United States.
Iluc
Vlad M
VM
Hillhouse
Gregory L
GL
D002245:Carbon Dioxide / Q000737:chemistry*; D002246:Carbon Disulfide / Q000737:chemistry*; D018360:Crystallography, X-Ray; D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry*; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry
D008024:Ligands; D009942:Organometallic Compounds; D002245:Carbon Dioxide; D009532:Nickel; D002246:Carbon Disulfide