In this letter, an unprecedented cross-coupling reaction between copper carbene and nitroso radical has been developed. This radical-carbene coupling reaction (RCC reaction) offers a novel approach for the preparation of various isoxazolines, which features the construction of C-C, C-O, and C═N bonds in a one-pot process. The synthetic utility of our method is further enhanced by its mild reaction conditions, wide substrate scope, and simple procedures.

Herein, we present a novel [3 + 2] cycloaddition reaction of β-keto esters with nitrile oxides, which were generated in situ from copper carbene and tert-butyl nitrite. This three-component reaction provides new methodology for the direct synthesis of fully substituted isoxazole derivatives, featuring mild reaction conditions, readily accessible starting materials and simple operation. The experimental studies and DFT calculations suggest that the reaction starts with the generation of the key intermediate nitrile oxides, followed by a [3 + 2] cycloaddition reaction of β-keto esters to give the final isoxazole products.

Through the interception of amide ylides with sulfonamides, we herein report the first general example of an intermolecular condensation reaction between sulfonamides and amides. Beyond formamides, this approach was successfully applied to a variety of lactams and linear amides, giving rise to a broad array of (E)-N-sulfonyl amidines.

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 NH 4 I. Under the optimized reaction conditions, a range of diazoesters and αdiazoketones 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.