Redox troponization of (η5-cyclopentadienyl)(η 4-4-methyl-4-exo-trichloromethylcyclohexa-2,5-dien-1-one)rhodium as a novel approach to the synthesis of metal-coordinated nonbenzenoid aromatics of the tropone series

Article abstract of DOI:10.1007/BF02503503

The possibility of redox troponization of a gem-polyhalomethylated semiquinoid system, π-coordinated to a metal atom, was shown in relation to the reaction of (η⁵-cyclopeniadienyl)(η ⁴-4-methyl-4-exo-trichloromethylcyclohexa-2,5-dien-1-one)rhodium with Pd(PPh₃)₄. The reaction occurs with retention of the metal coordination affording a seven-membered organometallic derivative of the nonbenzoid aromatic series, namely, (η⁵-cyclopentadienyl)(η ⁴-4-chloro-5-methylcyclohepta-2,4,6-trien-1-one)rhodium, whose structure was established by means of elemental analysis, NMR, and mass-spectral data.