FeCl2/TBAC efficiently catalyzes domino coupling reactions for constructing indoline-fused tetrahydroisoquinolines†
Abstract
FeCl2/TBAC has been found to be highly active for the construction of indoline-fused tetrahydroisoquinolines using aryltetrahydroisoquinolines and active methylene as simple reactants. The transformation was proposed to proceed via domino coupling reactions between Csp3–H and Csp3–H, and subsequently Csp3–H and Csp2–H, respectively. The EPR spectra have been acquired to analyse the catalytically active species, Fe3+OO˙ and Fe3+, which accelerated the reaction via HAT and SET processes, respectively.