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Context: Nickel-catalyzed hydroamination of dienes with phenylmethanamines was studied theoretically to investigate reaction mechanism. These calculated results revealed that Ni-catalyzed hydroamination began with the O − H bond activation of trifluoroethanol, including three important elementary steps: the ligand-to-ligand hydrogen migration, the nucleophilic attack of phenylmethanamine, and hydrogen migration. The nucleophilic attack of phenylmethanamine was the rate-determining step, and the branched product of 3,4-addition with (S)-chirality was the most dominant. The N − H bond activation of phenylmethanamine occurred more difficultly than the O − H bond of trifluoroethanol, because of high ΔG and ΔG≠. In addition, the origin of regioselectivity and enantioselectivity, and prediction of the ligand were also discussed in this text. Methods: All computations were performed with Gaussian09 program. All geometries were optimized at the ωB97XD/6-31G(d,p) level (SDD for Ni), and to obtain more accurate potential energy, single-point calculation was carried out at the ωB97XD/cc-pVDZ level (SDD for Ni). The Cramer-Truhlar continuum solvation model (SMD) was used to evaluate solvation effect of mesitylene, and a correction of the translational entropy was made with the procedure of Whitesides group. [ABSTRACT FROM AUTHOR]

• RPB was used for the synthesis of bisphenol S by reactive dehydration. • The optimal operating conditions for bisphenol S synthesis in RPB were studied. • The yield and content of bisphenol S could reach 86.65% and 96.38%, respectively. In this work, the synthesis of bisphenol S (4,4′-BPS) using reactive dehydration in a rotating packed bed (RPB) was studied. Firstly, orthogonal experiments were adopted to investigate the effects of different operating conditions on the yield and content of 4,4′-BPS in a stirred tank reactor (STR), including the mesitylene/phenol molar ratio (μ), reflux dehydration time (t), and stirring speed (n), in order to optimize the operating conditions in STR. Based on the study in STR, the effects of operating conditions, including rotation speed (N), feeding rate (q), and cycle number (τ), on the yield and content of 4,4′-BPS in RPB combined with STR (RPB-STR) were further investigated to optimize the operating conditions. The results indicated that compared to STR, the yield and content of 4,4′-BPS increased by 22.1% and 7.52% under the optimal operating conditions in RPB-STR, respectively. This work provides a novel route for efficient synthesizing 4,4′-BPS. [ABSTRACT FROM AUTHOR]