Oxidative Coupling of Diazo and NH4I: A Route to Primary Oxamates and α-Ketoamides.

A simple and efficient method has been developed for the preparation of primary oxamates and α-ketoamides through the oxidative coupling of diazo compounds and NH4I. Under the optimized reaction conditions, a range of diazoesters and α-diazoketones was explored, and the corresponding products were obtained in moderate to good yields. This protocol is metal-free, is performed under mild conditions, has a wide substrate scope, and offers operational simplicity.

Cross coupling of sulfonyl radicals with silver-based carbenes: a simple approach to ß-carbonyl arylsulfones.

A coupling reaction between sulfonyl radicals and silver-based carbenes has been well established. This simple radical-carbene coupling (RCC) process provided an efficient approach to a variety of ß-carbonyl arylsulfones from sodium arylsulfinates and diazo compounds, and was characterized by wide substrate scope, easy scale-up, simple manipulation, accessible starting materials, and mild reaction conditions.

Visible-Light-Induced Vicinal Dichlorination of Alkenes through LMCT Excitation of CuCl2.

This work demonstrates photoredox vicinal dichlorination of alkenes, based on the homolysis of CuCl2 in response to irradiation with visible light. This catalysis proceeds via a ligand to metal charge transfer process and provides an exciting opportunity for the synthesis of 1,2-dichloride compounds using an inexpensive, low-molecular-weight chlorine source. This new process exhibits a wide substrate scope, excellent functional group tolerance, extraordinarily mild conditions and does not require external ligands. Mechanistic studies show that the ready formation of chlorine atom radicals is responsible for the facile formation of C-Cl bonds in this synthetic process.

Rapid Interception of Cn F2n+1 (O)SO. Radical with Copper-Based Carbene: A Novel Access to Perfluoroalkanesulfinate Ester.

In this communication, an unprecedented interception of Cn F2n+1 (O)SO. radical with a copper-based carbene has been established. Distinguished by wide substrate scopes and mild reaction conditions, this novel radical-carbene coupling reaction (RCC reaction) provides a fundamentally different and mechanistically interesting strategy for the synthesis of perfluoroalkanesulfinate esters.

[3 + 3]-Cycloaddition of α-Diazocarbonyl Compounds and N-Tosylaziridines: Synthesis of Polysubstituted 2 H-1,4-Oxazines through Synergetic Catalysis of AgOTf/Cu(OAc)2.

An impressive and new [3 + 3]-cycloaddition of α-diazocarbonyl compounds with N-tosylaziridines via synergetic catalysis of AgOTf and Cu(OAc)2 has been well described, which offers efficient access to highly substituted 2 H-1,4-oxazine derivatives. A variety of α-diazocarbonyl compounds and N-tosylaziridines were compatible substrates with convenient operations under mild reaction conditions.

Interception of Radicals by Molecular Oxygen and Diazo Compounds: Direct Synthesis of Oxalate Esters Using Visible-Light Catalysis.

The synthesis of oxalate esters through a radical process, rather than the traditional ionic reaction, has been well developed in which the radicals induced by visible light are trapped by molecular oxygen and diazo compounds under room temperature. This reaction is operationally simple, mild, and shows broad substrate scopes in α-bromo ketones and diazo compounds.

[3 + 2] Cycloaddition of Nitrile Ylides with Diazonium Salts: Copper-Catalyzed One-Pot Synthesis of Fully Substituted 1,2,4-Triazoles.

A novel [3 + 2] cycloaddition between nitrile ylides and diazonium salts was well-established. This copper-catalyzed three-component reaction was distinguished by mild conditions, ready availability, and operational simplicity, thus opening access to 1,2,4-triazoles with a diverse set of substitution patterns.