Synthesis, structure, and haptotropic rearrangement of benzocyclo-octatetraenetricarbonylchromium (0) complexes

Abstract

The two tricarbonylchromium isomers of benzocyclo-octateraene complexed at the benzo ring (1) and at the eight-membered ring (2) have been synthesized. Their structure in solution was determined from a ¹H and ¹³C n.m.r. study. In addition, crystal structures of (1) and (2) have been determined by X-ray analysis. Rate constants and activation parameters have been measued for the migration of tricarbonylchromium from the eight-to the six-membered ring of benzocyclo-octatetraene in decalin and di-n-butly ether.