Copper‐Catalyzed Direct Cross‐Coupling of Compounds Containing Activated C–H/Heteroatom–H Bonds with N‐Tosylhydrazones

Abstract

Direct coupling between N-tosylhydrazones and various coupling partners such as 1,3-azoles, alkynes, and heteroatoms in the presence of Cu catalysts has turned out to be an extremely attractive route for carbon-carbon and carbonheteroatom bond formation. Recently, both intra-and intermolecular versions, along with cascade reactions involving sequential inter-and intramolecular coupling, have made a significant impact in synthetic chemistry. Emphasis has been placed on

Emerging Trends in N‐Tosylhydrazone Mediated Transition‐Metal‐Free Reactions

“…Here, we represent metal‐free cyclization processes of N ‐tosylhydrazones are simple to run, economical, sustainable, and produce outstanding results at a reasonable cost [18] . Recently, research has focused on annulation, [19] cycloaddition, [20] olefination„ [21] and X−Y insertion [22] . Under basic conditions, N ‐tosylhydrazones produce diazo intermediates that often undergo nucleophilic or electrophilic addition reactions to yield products with C−C and C−X bonds [23] .…”

[2 + 2 + 1] Cycloaddition of N-tosylhydrazones, tert-butyl nitrite and alkenes: a general and practical access to isoxazolines

“…1 Over the past several decades, N -tosylhydrazones, which are readily obtained from ketones or aldehydes, have rapidly become a new type of versatile synthon for transition metal-catalysed or metal-free reactions. 2 Since the pioneering work by Barluenga, 3 m –3 p a wide range of transformations using N -tosylhydrazones has been established, including coupling, 3 insertion, 4 cyclization, 2 e ,5 olefination 6 and alkynylation 7 reactions, and these are now standard methods in organic synthesis. Although this unconventional manipulation of carbonyl compounds provides powerful and indispensable protocols for the facile construction of diverse molecular frameworks, this rapidly evolving area is still far from mature and there is ample opportunity for further development.…”

Immobilization of copper complexes with (1,10-phenanthrolinyl)phosphonates on titania supports for sustainable catalysis

“…[1][2][3] This is of major importance in view of societal concerns relating to environmental and sustainable chemistry. In the last two decades, signicant improvements in homogeneous Cu-catalysed C-C 4-7 and C-Het (Het ¼ O, S, Se, N, P) 6,8 cross-coupling reactions, additions to unsaturated C-C bonds, 9 Huisgen 1,3-dipolar cycloaddition, 10 and other organic transformations 2,9,[11][12][13][14][15] were reported. Homogeneous catalysts are well suited for increasing the reaction scope and ne tuning the reaction rate and its selectivity.…”