Lewis Acid-Promoted Oxidative Cleavage of Carbon-Carbon Bonds: Synthesis of N-Arylated Lactam-Type Iminosugars.

In this paper, a mild strategy for the oxidative cleavage of carbon-carbon bonds catalyzed by Lewis acid was developed in air condition at room temperature. Under such conditions, the bis-carbonyl compounds 3 were directly afforded from the reaction of D-ribose tosylate 1 and aniline in excellent yields through the oxidative cleavage of the key intermediate iminium-ion A and its tautomer enamine B. A series of N-arylated lactam-type iminosugars 5 were then successfully obtained by removing the isopropylidene group from 3 with the aid of the condensation agent DCC. Additionally, reduction of A and the removal of the isopropylidene group could provide N-arylated iminosugars 4. This strategy enables the oxidative cleavage of carbon-carbon bonds under mild conditions and facilitates the synthesis of the novel iminosugars with potent biological activity.

One-Pot Stereoselective Synthesis of Furantetrahydroquinoline Derivatives Using d/l-Ribose with a 2,3-O-Isopropylidene Group.

An efficient and convenient strategy has been successfully developed for the preparation of novel furantetrahydroquinoline derivatives using d/l-ribose with a 2,3-O-isopropylidene group through the aza-Diels-Alder mechanism. This method has high atom and step economy, high stereoselectivity, and gram-scale synthesis (yield 67%).

Correction: Iron-promoted free radical cascade difunctionalization of unsaturated benzamides with silanes.

Correction for 'Iron-promoted free radical cascade difunctionalization of unsaturated benzamides with silanes' by Yaxin Ge et al., Chem. Commun., 2020, 56, 12656-12659, https://doi.org/10.1039/D0CC05213B.

Iron-promoted free radical cascade difunctionalization of unsaturated benzamides with silanes.

Iron salt/peroxide promoted cascade difunctionalization of unsaturated benzamides with silanes has been reported. It provides a convenient, highly selective, and efficient protocol for the synthesis of various silylated dihydroisoquinolinones and 1,3-isoquinolinediones. In particular, the present methodology only gives cyclization products in good isolated yields under the typical conditions.

Silver or cerium-promoted free radical cascade difunctionalization of o-vinylanilides with sodium aryl- or alkylsulfinates.

An efficient cascade oxysulfonylation of o-vinylanilides with sodium aryl- or alkylsulfinates by a free radical mechanism has been developed, which provides a mild, facile and convenient method for the synthesis of various benzoxazines. Control experiments, including gram-level reactions and mechanistic studies, are involved in the reaction system.