Aerobic dehydrogenation of amines to nitriles catalyzed by triazolylidene ruthenium complexes with O₂ as terminal oxidant

Abstract

Pyridyl-substituted mesoionic triazolylidene ruthenium cymene complexes catalyze the oxidation of both aromatic and aliphatic amines to nitriles with high activity and selectivity under benign conditions using dioxygen as the terminal oxidant.

Synthesis and Characterization of 3‐(Aryl azo)‐4‐hydroxy‐1,2‐naphthoquinone Ruthenium(III) Complexes as Catalysts for Benzyl Alcohol Oxidation

“…It is always important to compare the results of the new work with those already published work to evaluate the novelty of the work. Therefore, efforts are made to compare the results of this article with those already published papers [15–28,42] . In this protocol, the yields of acids were comparable with those reported by Sarkar et al [42] .…”

“…[14] . It is interesting to mention here that among them ruthenium‐based catalysts are considered as the best ones because of their significant activities, [15–20] high efficiency and selectivity [21–23] . A series of substituted benzyl alcohol are catalytically oxidized to their acids by refluxing them with Ru 3 (CO) 8 (C 5 H 4 NCO 2 ) 2 complex in the aqueous isopropanol at 98 °C for 14 h [17] .…”

Synthesis, stability, and reactivity of mesoionic carbene iridium dihydride complexes

“…Synthesis and characterization of a series of dihydride iridium complexes with mesoionic carbene ligands. Metalation of the known 16,17 triazolium salts 1-3 was accomplished upon reaction with IrH5(PPh3)2 in toluene at elevated temperature (Scheme 1), similar to related work with imidazolium salts. 18 These conditions induced triazolium C-H bond activation via cyclometalation and afforded complexes 4-6 as pale yellow solids.…”

Methods of Nitriles Synthesis from Amines through Oxidative Dehydrogenation

“…Later, Taube and co‐workers carried out a detailed study on the oxidation of different types of amine ligands coordinated to ruthenium centers . Based on these initial findings, numerous ruthenium catalyzed methods have been reported for the ODH of amines to nitriles (Table ) …”

“…The activity and stability of the catalyst was affected by the substituents attached to the ligands. Modification on the pyridyl ligand has negligible effects on catalytic performance, while substituents on the triazolylidene directly affect the catalyst stability and activity . Most recently, in 2020: a ruthenium complex [(6‐BrPyCHRO) 2 Ru 3 (CO) 8 ] carrying N,O‐bidentate ligands for the ODH of primary benzylic amines to amides and nitriles in the presence of t ‐BuOK was investigated (Scheme ) .…”