Co-oligomerization of diphenylketene and ethylene promoted by (η5-cyclopentadienyl)bis(ethylene)cobalt(I): synthesis and X-ray structure of a heterocycle containing cobalt(III)
Abstract
The complex [Co(cp)(C2H4)2](cp =η5-C5H5) promotes the co-cyclization of two diphenylketenes and one ethylene molecule to form a chelate ring which is a structural model for some precursors of metal-catalyzed co-cyclization of different functionalities. The X-ray structure of the resulting complex [[graphic omitted]}(cp)], (2), shows the sequence of co-oligomerization of the three molecules. The cobalt is η5 bonded to cp, η3 bonded to an allyl group (arising from the rearrangement of an ethylene residue), and bonded to an oxygen atom. Complex (2) crystallizes in the triclinic space group P, with α= 12.664(4), b= 16.637(5), c= 10.378(4)Å, a= 93.60(4), β= 113.27(3), γ= 93.83(4)°, Z= 2, R= 0.065.