Search

Typical algorithms for deep learning include DNN (deep neural network), CNN (convolution neural network), and RNN (recurrent neural network) algorithms. Among them, RNN is excellent at dealing with sequential data. Sequential data such as time series data can be handled without losing gradient by LS...

The catalytic activity of a series of Ru-PNP pincer ligand complexes was studied in the direct amination of alcohols with ammonia. It turned out that all complexes of PNP ligands bearing a secondary amine showed no activity in this hydrogen-shuttling reaction sequence, while all complexes of homologous ligands bearing a tertiary amine gave active catalysts. Further comparative studies on catalysts bearing an acridine-based PNP pincer ligand and a PNP ligand of the Xantphos family provided valuable mechanistic insight that led to the design of a highly active catalyst. It appears that in the group of ligands studied here only ligands that do not form stable Ru-amido complexes are active alcohol amination catalysts.

The selective hydrogenation of aromatic and aliphatic nitriles into amines and imines is described. Using a ruthenium pincer complex, the selectivity towards amines or imines can be controlled by simple parameter changes. The reactions are conducted under very mild conditions between 50–100 °C at 0.4 MPa H2 pressure without any additives at low catalytic loadings of 0.5–1 mol %, which results in quantitative conversions and high selectivity.

By adjustment of the reaction parameters an efficient transformation of aromatic and aliphatic nitriles into amines or imines is achieved.