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BPh3 catalyzes the N‐methylation of secondary amines and the C‐methylenation (methylene‐bridge formation between aromatic rings) of N,N‐dimethylanilines or 1‐methylindoles in the presence of CO2 and PhSiH3; these reactions proceed at 30–40 °C under solvent‐free conditions. In contrast, B(C6F5)3 shows little or no activity. 11B NMR spectra suggested the generation of [HBPh3]−. The detailed mechanism of the BPh3‐catalyzed N‐methylation of N‐methylaniline (1) with CO2 and PhSiH3 was studied by using DFT calculations. BPh3 promotes the conversion of two substrates (N‐methylaniline and CO2) into a zwitterionic carbamate to give three‐component species [Ph(Me)(H)N+CO2−⋅⋅⋅BPh3]. The carbamate and BPh3 act as the nucleophile and Lewis acid, respectively, for the activation of PhSiH3 to generate [HBPh3]−, which is used to produce key CO2‐derived species, such as silyl formate and bis(silyl)acetal, essential for the N‐methylation of 1. DFT calculations also suggested other mechanisms involving water for the generation of [HBPh3]− species. [ABSTRACT FROM AUTHOR]

RutheniumII complexes bearing three axially chiral bipyridyl ligands were synthesized as a new family of chiral complex dyes, and Δ‐(S)‐ and Λ‐(S)‐diastereomers were obtained. The X‐ray crystal structure analyses, spectroscopy, and DFT calculations suggested that all the bipyridyls maintained chirality in both the ground and excited states, and the Δ‐(S)‐ and Λ‐(S)‐isomers are the matched (more relaxed) and mismatched (more constrained) pairs, respectively. The mismatched Λ‐(S)‐isomer exhibited red circularly polarized phosphorescence (CPP) both in solution and in the solid state. The solution state CPP is the most intense of ruthenium complexes, while the solid state CPP is the first example of them. It is supposed that, for the Λ‐(S)‐isomer, the six cumulative CH/π interactions suppress further distortion in the T1 state. [ABSTRACT FROM AUTHOR]