[Zurück]

R. Pollice, N. Dastbaravardeh, N. Marquise, M.D. Mihovilovic, M. Schnürch:
"Mechanistic and kinetic studies of the direct alkylation of benzylic amines - A formal C(sp3)-H activation proceeds actually via a C(sp2)-H activation pathway";
ACS Catalysis, 5 (2015), S. 587 - 595.

Mechanistic investigations of a Rh(I)-catalyzed direct C−H alkylation
of benzylic amines with alkenes, formally an C(sp3)−H activation, reveal this reaction to proceed via imine intermediates and, hence, via C(sp2)−H activation. The reaction shows a primary kinetic isotope effect of 4.3 at the benzylic C−H position together with a reversible H−D exchange at the same position, which indicates that there are at least two distinct steps in which the corresponding C−H bonds are broken. The imine intermediates are shown to be converted to the final product under the reaction conditions, and a time course analysis of the alkylated imine intermediate

heterogeneous reaction, Rh(I) catalysis, C−H activation, cyclometalation, direct alkylation, kinetic isotope effects, reaction mechanism

http://dx.doi.org/10.1021/cs501924c

http://publik.tuwien.ac.at/files/PubDat_241512.pdf