Synthesis of Functionalized Ferrocene Derivatives from Donor-Acceptor Cyclopropanes.

The TfOH-catalyzed reaction of aryl-substituted donor-acceptor cyclopropane derivatives with ferrocene provided new functionalized ferrocene derivatives. This process exhibited a reasonable scope with respect to the cyclopropane component affording the corresponding alkylated ferrocene derivatives in useful yields. An alternative approach to these functionalized ferrocene derivatives involving arylation of a ferrocene-decorated donor-acceptor cyclopropane derivative is also disclosed. Both processes rely on a facile regioselective ring-opening of the donor-acceptor cyclopropane.