A range of carbon-donor nucleophiles add to the arene ring in (arene)Mn(CO)2L+ cations to give neutral cyclohexadienyl complexes that liberate monofunctionalized arenes upon oxidative removal of the metal. Treatment of the cyclohexadienyl complexes with the nitrosonium salt NOPF6 affords cationic metal nitrosyl complexes that are attacked by a second nucleophile to give cis- and trans-difunctionalized 1,3-cyclohexadienes. When the metal center is chiral, this procedure provides a route to enantiomerically pure cyclohexadienes. 1. Introduction 2. Mechanism of Nucleophilic Addition 3. Single Nucleophilic Addition 4. Double Nucleophilic Addition 5. Conclusions
Pike, Robert D. and Sweigart, D. A., Single and Double Nucleophilic-Addition to Coordinated PI-Hydrocarbons - Manganese-Mediated Functionalization of Arenes (1990). Synlett, 10, 565-571.