Metal stabilized carbanions. XIII. The mechanism of migration of the Cr(CO)3 unit from the six- to the five-membered ring in indenyl anions

Article abstract of DOI:10.1016/0022-328X(91)86045-R

The potassium salts of η⁶-indenyl-, η⁶-(1-phenyl)indenyl-, and η⁶-(1,3-diphenyl)indenyl-Cr(CO)3 anions have been prepared in THF solution at -30 deg C and fully characterized by 1H NMR spectroscopy.At higher temperatures, the Cr(CO)3 group migrates from the benzo- to the cyclopentadienyl-ring, the migration being slowest for the 1,3-diphenyl-substituted species.A kinetic study indicates that an intra-molecular pathway through an η³ intermediate is preferred.