Concurrent Formation of N–H Imines and Carbonyl Compounds by Ruthenium-Catalyzed C–C Bond Cleavage of β-Hydroxy Azides

Abstract

A commercial cyclopentadienylrutenium dicarbonyl dimer ([CpRu­(CO)2]2) efficiently catalyzes the formation of N–H imines and carbonyl compounds simultaneously from β-hydroxy azides via C–C bond cleavage under visible light. Density functional theory calculations for the cleavage reaction support the mechanism involving chelation of alkoxy azide species and liberation of nitrogen as the driving force. The synthetic utility of the reaction was demonstrated by a new amine synthesis promoted by chemoselective allylation of imine and synthesis of isoquinoline.

Reactivity of Styrenes in Micelles: Safe, Selective, and Sustainable Functionalization with Azides and Carboxylic Acids

“…The versatility of this aqueous technology was further explored for one-pot carbonyl reductions and copper-catalyzed 1,3-dipolar cycloaddition between resulting azides and alkynes (Table ). , In other words, without isolation of α-azidoketones, carbonyl reduction and cycloaddition reactions were performed in the same pot. For carbonyl reductions, azide remained intact upon reaction with NaBH 4 ( 26 – 28 ).…”

Generation of N–H Imines from α-Azidocarboxylic Acids through Ru-Catalyzed Decarboxylation

“…In addition to the substrate scope, we studied the reaction mechanism using DFT calculations (Scheme S1). The calculated reaction profile closely resembles the α-azidoalcohol case and involves photodissociation of a CO ligand from the ruthenium center, followed by substrate coordination and ruthenium dimer splitting to generate the catalytically active species. In two subsequent essentially barrierless steps, nitrogen and carbon dioxide molecules are liberated providing the driving force of the process.…”

“…Various alkyl and aryl N–H imines could be obtained and utilized in subsequent transformations. Recently, we demonstrated that α-azidoalcohols undergo a Ru-catalyzed C–C bond cleavage, providing the corresponding N–H imine and aldehyde or ketone as products . Compared to our previous reports, this reaction proceeded in the presence of a commercially available catalyst and the reaction time was considerably shorter (typically 1 h).…”

“…Recently, we demonstrated that α-azidoalcohols undergo a Ru-catalyzed C−C bond cleavage, providing the corresponding N−H imine and aldehyde or ketone as products. 7 Compared to our previous reports, this reaction proceeded in the presence of a commercially available catalyst and the reaction time was considerably shorter (typically 1 h). However, in this case, our attention focused on the aldehyde/ ketone products that could be conveniently isolated due to their high stability as compared to the N−H imine counterparts.…”

“…This compound could be prepared on a gram scale (92% yield, 1.09g) Yield: 99% (27.1 mg), white solid. 1 7,141.6,128.8,128.5,127.3,126.6,126.2,121.3,118.2,115.1,68.7,2,3,phenol (6f). 18c Flash column chromatography was carried out on silica gel (230−400 mesh) as the stationary phase.…”