D. Bonnetdelpon et al., USE OF A CHROMIUM TRICARBONYL COMPLEX IN A DIELS-ALDER REACTION - IMPROVED PREPARATION OF ANGULARLY TRIFLUOROMETHYL-SUBSTITUTED TETRAHYDROPHENANTHRONE, Applied organometallic chemistry, 8(6), 1994, pp. 551-552
The tricarbonyl complex prepared from 1-trifluoromethyldihydronaphthal
ene and Cr(CO)3(NH3)3 undergoes Diels-Alder cycloaddition under high-p
ressure conditions (15 kbar) to give after decomplexation by natural l
ight and deprotection, the tetrahydrophenanthrone product in 65% yield
. This new methodology allows the activation of unreactive styrenes in
Diels-Alder cycloaddition.