Nuclear recoil synthesis of metallorganic compounds and crystal structure of Co3(CO)9(C6H7)

The formation of the complexes Co2(CO)6(C6H8) (I) and Co3(CO)9(C6H7) (II) by nuclearrecoil of 60Co and T is reported together with the crystal structure of II. The very low T activity found in II suggests that benzvalene species play an important role in the formation of II. The crystal structure of II has been determined by X-ray diffraction methods. Crystals are triclinic, space group P, a = 8.593(4), b = 14.305(7), c = 8.144(5) Å, α=95.28(2), β = 112.24(2), γ = 100.78(2)°. The structure has been solved from diffractometer data by direct and Fourier methods and refined by full-matrix least-squares to R = 0.0578 for 1456 observed reflections. The structure consists of an equilateral triangular cluster of Co atoms [CoCo bond distances: 2.450(3), 2.451(3) and 2.459(3) Å]. A carbon atom from the (2-cyclopenten-1-methylidine) ligand nearly symmetrically caps the metal triangle [CoC bonds: 1.883(11), 1.901(11) and 1.902(14) Å].