Ruthenium‐Catalyzed Direct Reductive Amination of Carbonyl Compounds for the Synthesis of Amines: An Overview

Abstract

Reductive amination is a valuable method for amine synthesis that has been the topic of a century's worth of in-depth study in both academia and industry. Amines and their derivatives serve as incredibly adaptable building blocks for a broad array of organic substrates and are significant precursors for a myriad of advanced chemicals, physiologically active compounds, agrochemicals, biomolecules, pharmaceuticals, and polymers. The creation of innovative catalytic processes for the long-term and selective synthesis of amines from readily accessible and environmentally benign reagents remains a top priority in chemical research. Both heterogeneous and homogeneous catalysts have been designed with success to enable these reactions to explore new amines. Ruthenium catalysts are employed in reductive amination owing to their stability, selectivity, versatility, low toxicity, and high efficiency. This review comprehensively overviews the Ru-catalyzed reductive amination processes and includes the literature from 2009 to 2022.

Chalcogen- and Halogen-Bond-Donating Cyanoborohydrides Provide Imine Hydrogenation

“…In this work, we have applied the electrophilic properties of organic σ-hole donors to hydrogenation of an imino group by the cyanoborohydride anion, which is a required process in a series of reductive amination reactions leading to industrially important products. ,, Considering this, herein we report the synthesis and characterization of chalconium, iodonium, and iodoazolium cyanoborohydrides, as well as the kinetic study clearly representing a significant acceleration of the reduction of model imine in the presence of the XB and ChB donors compared to sodium and tetrabutylammonium cyanoborohydrides.…”

Efficient Synthesis of Ractopamine‐D3 via Epoxide‐Opening Strategy

“…Currently, there have been several reports on the synthesis of deuterium-labeled ractopamine using Borch reduction [16] or nucleophilic substitution. [17] In 2012, Lu and co-workers patented deuterated ractopamine by reacting labeled octopamine and raspberry ketone, and dehydration reduction (Scheme 1a).…”