This data was assembled to investigate rare-earth-catalyzed benzylic C(sp3)-H addition of pyridines to olefins. All calculations were performed with the Gaussian 09 software package. The B3PW91 functional was used for geometric optimization without any symmetric constraints. Each optimized structure was subsequently analyzed by harmonic vibrational frequencies at the same level of theory for characterization of a minimum (NImag = 0) or a transition state (NImag = 1) to obtain the thermodynamic data. The 6-31G(d) basis set was used for C, H, and N atoms, and Stuttgart/Dresden relativistic effective core potentials (RECPs) as well as the associated valence basis sets were used for the Y atom. To obtain more accurate energies, single-point energy calculations were performed with a larger basis set. In such single-point calculations, the M06-L functional, which often shows good performance in the treatment of transition-metal systems, was used together with the CPCM solvation model for consideration of the