18503-48-5

Usage

Synthesis Reference(s)

Tetrahedron, 46, p. 2525, 1990 DOI: 10.1016/S0040-4020(01)82033-0

Upstream product

• 91-19-0 2,3-diethynylquinoxaline 
• 507-19-7 t-butyl bromide 
• 35448-10-3 oxalic acid mono-tert-butyl ester 
• 98-89-5 Cyclohexanecarboxylic acid 
• 108163-91-3 2-t-butyl-1,2-dihydroquinoxaline 
• 6832-15-1 1-diazo-3,3-dimethyl-2-butanone 
• 95-54-5 1,2-diamino-benzene 
• 59562-82-2 3,3-dimetylbutan-1,2-diol 
• 95-14-7 1,2,3-Benzotriazole 
• 917-92-0 3,3-Dimethylbut-1-yne 
• 142321-29-7 1-(hex-1-en-2-yl)-1H-benzo[d][1,2,3]triazole 
• 23269-74-1 1-[1-(phenyl)vinyl]-1H-benzo[d][1,2,3]triazole 
• 3282-30-2 pivaloyl chloride 
• 88-74-4 2-nitro-aniline 

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An ultrastable olefin-linked covalent organic framework for photocatalytic decarboxylative alkylations under highly acidic conditions

The application of two-dimensional covalent organic frameworks (2D-COFs) as photoredox catalysts offers sustainable alternatives for visible-light-driven organic transformations. However, under highly complicated organic reaction conditions, maintaining their basic structure and photoactivity is always neglected, which impedes their potential in more organic reaction types and industrial use. Herein, we describe a visible-light-driven decarboxylative alkylation of heterocycles catalysed by an olefin-linked covalent organic framework (2D-COF-2) instead of the commonly used precious metal complexes and organic dyes. A wide range of alkylated heterocycles were selectively and efficiently synthesized under heterogeneous reaction conditions. Relying on the ultrastability of olefin linkage, 2D-COF-2 maintained its basic structure and photoactivity under highly acidic conditions. Moreover, its streamlining industrial potential was demonstrated in recycling experiments, functionalization of bioactive molecules and scale-up reactions.

Iron-catalyzed one-pot synthesis of quinoxalines: Transfer hydrogenative condensation of 2-nitroanilines with vicinal diols

Here, we report iron-catalyzed one-pot synthesis of quinoxalines via transfer hydrogenative condensation of 2-nitroanilines with vicinal diols. The tricarbonyl (η4-cyclopentadienone) iron complex, which is well known as the Kn?lker complex, catalyzed the oxidation of alcohols and the reduction of nitroarenes, and the corresponding carbonyl and 1,2-diaminobenzene intermediates were generated in situ. Trimethylamine N-oxide was used to activate the iron complex. Various unsymmetrical and symmetrical vicinal diols were applied for transfer hydrogenation, resulting in quinoxaline derivatives in 49-98% yields. A plausible mechanism was proposed based on a series of control experiments. The major advantages of this protocol are that no external redox reagents or additional base is needed and that water is liberated as the sole byproduct. This journal is

Iridium-Catalyzed [4+2] Annulations of β-Keto Sulfoxonium Ylides and o-Phenylenediamines: Mild and Facile Synthesis of Quinoxaline Derivatives

A synthetic method for quinoxaline derivatives from the [4+2] annulation of β-keto sulfoxonium ylides and o-phenylenediamine by using (Cp*IrCl2)2 catalyst is described. This novel protocol features mild reaction conditions, moderate to excellent yields, wide substrate scope, and high functional-group compatibility. Moreover, this cyclization strategy was successfully applied in late-stage modification for structurally complex bioactive compounds.

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Nickel-Catalyzed Direct Synthesis of Quinoxalines from 2-Nitroanilines and Vicinal Diols: Identifying Nature of the Active Catalyst

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Design and implementation of a catalytic electron donor?acceptor complex platform for radical trifluoromethylation and alkylation

Electron donor?acceptor (EDA) complexes can controllably generate radicals under mild conditions through selective photoexcitation events. However, unproductive reactivity from fast deactivation of the photoexcited complexes through back electron transfer has slowed the development of EDA complexes in synthetic methodology. Here, we disclose the study of EDA complexes derived from 2-methoxynaphthalene donor and acylated ethyl isonicotinate N-oxide acceptor that undergo a fast N?O bond fragmentation event upon photoexcitation. This reaction design not only overcomes the limitations of back electron transfer but also enables regeneration of the donor species, representing a rare example of EDA photochemistry in a catalytic regime. The synthetic utility is demonstrated through visible light-driven radical trifluoromethylation and Minisci alkylation reactions. The scalability of the EDA complex-promoted reaction is evidenced by the successful multigram-scale trifluoromethylation of methyl N-Boc pyrrole-2-carboxylate in a continuous flow manifold.

Mn(II)-catalyzed C-H alkylation of imidazopyridines and N-heteroarenes via decarbonylative and cross-dehydrogenative coupling

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