Ruthenium-catalyzed addition of 3′-methyl-, 3′-trifluoromethyl-, and 3′-N,N-dimethylaminoacetophenones to an olefin proceeds site selectively at 6′ CH bonds to give the 1:1 CH/olefin addition products in high yields. In contrast, the addition of 3′-methoxyacetophenone takes place preferentially at the CH bond at the more congested 2′ position.