Evidence for metal induced bond localization in cyclobutabenzenes: the crystal and molecular structures of h6-Cr(CO)3 and h4-Fe(CO)3 complexes of cyclobutabenzene.
In: Journal of Organometallic Chemistry, Jg. 542 (1997) ; Nr. 1, S. 19-24
Zeitschriftenaufsatz / Fach: Chemie
The crystal and mol. structure of the title compds. were detd. at low temps. The accuracy of the structures allows for a discussion about the bond alternation in the six-membered ring. Both complexes show bond localization, whereas the benzocyclobutene-Cr(CO)3 shows localization in the Mills-Nixon effect manner, the benzocyclobutadiene-Fe(CO)3 shows an anti-Mills-Nixon localization.