A combined experimental–theoretical study on the lithiation/electrophilic quench reaction of benzylic position of (η5-tetramethylcyclohexadienyl)-Mn(CO)3
A combined experimental–theoretical study on the lithiation/electrophilic quench reaction of benzylic position of (η5-tetramethylcyclohexadienyl)-Mn(CO)3
[(eta(6)-Pentamethylbenzene)Mn(CO)(3)](+) BF4- and [(eta(6)-1,2,4,5-tetramethylbenzene)Mn(CO)(3)]+BF4- 2 complexes were prepared and reacted with nucleophiles to provide neutral exo-substituted (eta(5)-polytnethylcyclohexadienyl)Mn(CO)(3) complexes 3-6. To study the regioselectivity of the deprotonation at a "benzylic" position of (eta(5)-methylcyclohexadienyl)Mn(CO)(3) complexes, compounds 3-6 were submitted to a lithiationl/electrophilic quench sequence, and functionalized complexes 9-18 were obtained in good yields and with a total regioselectivity. A second sequence gave rise to the formation of unprecedented bifunctionalized (eta(5)-1,2,4,5-tetramethylcyclohexadienyl)Mn(CO)(3) and (eta(5)-pentamethylcyclohexadienyl)Mn(CO)(3) complexes 19-22.