To further demonstrate the synthetic utility of this protocol, a gram-scale reaction was conducted. As shown in Scheme 2, the reaction of 40 mmol of A8 with 4 mmol of B1 in the presence of 10 mol% of Sc-3 proceeded smoothly, furnishing the corresponding C(sp 3 )-H alkylation product D8 in 90% isolated yield (1.14 g). Epoxidation and dihydroxylation of D8 were carried out, the corresponding products were furnished in high yield with moderate diastereoselectivity (Scheme 2a, 88% yield for G1, 86% yield for G2). The hydrosilylation reaction occurred efficiently under the influence of La[(N(SiMe3)2]3, the product was isolated in 68% yield. Scale-up experiments of A11 and A18 with B1 were also performed. The Suzuki coupling reaction of D18 with 2-furylboronic acid afforded the desired product G4 with 82% yield (Scheme 2b). Taking use of C-H alkylation of N,N-dimethyl aniline developed by our group, 11d the C(sp 3 )-H alkylation product G5 was afforded in 68% yield in the presence of Sc-1 (Scheme 2c). The C(sp 2 )-H alkylation product G6 was obtained in 15% yield in the presence of Sc-8. Scheme 2. Scale-Up Synthesis of Products and Their Further Transformations Mechanistic Studies. To gain more insights into the mechanism of allylic C(sp 3 )-H bond activation, a set of control experiments were carried out. As shown in Scheme 3a, the isomerization of pure E or Z-β-methylstyrene (A1) and the transposition of allylbenzene (B2) to βmethylstyrene were performed under the influence of Sc-3. β-Methylstyrene with 13:1 E/Z ratio was obtained for both cases after 12 h. These results implied the same intermediate may be formed in the reaction process. The effect of configuration of β-methylstyrene (A1) on the crosscoupling reaction with styrene were investigated (Scheme 3b). The use of Z-β-methylstyrene or a Z/E mixture of βmethylstyrene led to comparable results (54% yield, 5.6:1 E/Z). Slightly lower yield was afforded for the reaction of pure E-β-methylstyrene (44% yield). Notably, the same E/Z ratio of 5.6:1 was obtained probably due to the fluxionality of allylic rare-earth metal intermediate. In addition, the rare-earth metal allyl complexes Sc-10 and Sc-11 were synthesized and subjected to the homo-coupling reaction. It was found that the use of Sc-3 provided the desired product C1 in 26% yield, but Sc-11 afforded high E/Z ratio (only E vs. 2.5:1 E/Z). In contrast, the addition of THF (10 mol%) dramatically increased the reactivity and E/Z selectivity (81% yield, >19:1 E/Z). These result implied that both coordinated THF and basic ligand displayed an impact on the reactivity and E/Z selectivity of the reaction (Scheme 3c). 11d