(A) Ru-catalyzed hydrogenation of acetophenone. (B) Lowest energy computed transition structure (ωB97X-D/SDD(Ru)/6-31G*(C,H,N,O,P,K)/SMD(propan-2-ol)) for rate- and selectivity-determining C–H bond formation catalyzed by amidato complex 105b. The proposed cation–π interaction is depicted by green dotted lines. Adapted with permission from ref. 91. Copyright 2014 American Chemical Society. (C) Revised catalytic cycle.