TY - JOUR
T1 - Synthesis, molecular structure, and dynamic behaviour in solution of octakis(t-butyl isocyanide)dicobalt
AU - Carroll, W. Eamon
AU - Green, Michael
AU - Galas, Anita M. R.
AU - Murray, Martin
AU - Turney, Terence W.
AU - Welch, Alan J.
AU - Woodward, Peter
PY - 1980
Y1 - 1980
N2 - Reduction of [Co(CNBut)5][PF6] with potassium amalgam in tetrahydrofuran affords red air-sensitive crystals of octakis(t-butyl isocyanide)dicobalt. Crystals of [Co2(CNBut)8] are orthorhombic, space group P21212, with two molecules in a cell of dimensions a = 18.017(4), b = 12.149(4), and c = 11.382(5) Å. The structure has been solved by conventional techniques and refined by least squares to R 0.085 for 2 376 reflection intensities recorded on a four-circle diffractometer. The molecular geometry resembles that of [CO2(CO)8], but is substantially distorted, especially with respect to one of the basal isocyanide functions. Non-bonded contacts calculated for an idealized molecular geometry strongly suggest the importance of intermolecular contacts in the adopted distortions. The cobalt-cobalt distance is 2.4567(20) Å. The 13C n.m.r. spectrum of an enriched (10%) sample of [Co2( CNBut)8] shows one resonance at ambient temperature collapsing (coalescence temperature -60 °C) to three resonances (1:1:2) at -90 °C. Evidence is presented for an intramolecular exchange process. Reaction of [Co2(CNBut)8] with CO, NO, and diphenylacetylene affords respectively [Co(CNBut)5][Co(CO)4], [Co(CNBut)3-(NO)], and [Co2{μ-(η2-PhC2Ph)}(CNBu t)6].
AB - Reduction of [Co(CNBut)5][PF6] with potassium amalgam in tetrahydrofuran affords red air-sensitive crystals of octakis(t-butyl isocyanide)dicobalt. Crystals of [Co2(CNBut)8] are orthorhombic, space group P21212, with two molecules in a cell of dimensions a = 18.017(4), b = 12.149(4), and c = 11.382(5) Å. The structure has been solved by conventional techniques and refined by least squares to R 0.085 for 2 376 reflection intensities recorded on a four-circle diffractometer. The molecular geometry resembles that of [CO2(CO)8], but is substantially distorted, especially with respect to one of the basal isocyanide functions. Non-bonded contacts calculated for an idealized molecular geometry strongly suggest the importance of intermolecular contacts in the adopted distortions. The cobalt-cobalt distance is 2.4567(20) Å. The 13C n.m.r. spectrum of an enriched (10%) sample of [Co2( CNBut)8] shows one resonance at ambient temperature collapsing (coalescence temperature -60 °C) to three resonances (1:1:2) at -90 °C. Evidence is presented for an intramolecular exchange process. Reaction of [Co2(CNBut)8] with CO, NO, and diphenylacetylene affords respectively [Co(CNBut)5][Co(CO)4], [Co(CNBut)3-(NO)], and [Co2{μ-(η2-PhC2Ph)}(CNBu t)6].
UR - http://www.scopus.com/inward/record.url?scp=37049105508&partnerID=8YFLogxK
U2 - 10.1039/DT9800000080
DO - 10.1039/DT9800000080
M3 - Article
AN - SCOPUS:37049105508
SN - 1472-7773
SP - 80
EP - 86
JO - Journal of the Chemical Society, Dalton Transactions
JF - Journal of the Chemical Society, Dalton Transactions
IS - 1
ER -