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Abstract In the chemistry of these satu- aturated-polycyclic aromatictricar
bonyl ch- romiumcomplexes., we find it includes high regio-selectivity, and th
ey have an obvious sign of C-H bond activation at proton NMR analysis. Beca
use of the electronic density distribution on polycyclic arenes, the reaction
mostly occurred on certain parts of the polycyclic ring, and their high electr
onic density and strong C-H bond strength will make the substitution reac- tio
n, especially the alkylation, become very difficult. After the coordination
of tricarbonyl chromium with polycyclic arene, the strong electron with drawi
ng character of metal will lower the electron density of arene, and activate t
he C-H bonding of arene, make the proton easier to substituted by lithium cati
on. We have found that the alkylation of these complexes will have the hig
h regio-selectivity, and the substitution occurred at coor-dinated ring sites.
Due to the easy demetallation of polycyclic aromatic tricarbonyl chromium
complexes, this type of organometallic synthesis procedures should be very use
ful at the synthetic field of organic chemist. We hope its farther appl
ication can be extended into the general synthesis reaction.
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