Photocatalyzed cross-dehydrogenative coupling of silanes with alcohols and water.

An efficient method for the dehydrogenative coupling of silanes with alcohols under photocatalysis was developed. The reaction proceeded in the presence of Ru(bpy)3Cl2 (0.5 mol%) under visible light irradiation in acetonitrile at room temperature. The developed methodology was also applicable for the synthesis of silanols using water as a coupling partner.

Progress in Visible Light-Induced Difluroalkylation of Olefins.

The incorporation of difluoromethylated (CF2 ) moiety into potentially useful parent molecules lead to significant changes in metabolic stability, lipophilicity, and solubility of the molecules. Over the past several years, with the advent of new difluoromethylating reagents, great progress has been made in the development of a protocol for the direct incorporation of the CF2 H group into organic molecules. Among them, difluroalkylation induced by visible light has emerged as an efficient strategy over the past few years. In particular, this protocol provides a more sustainable alternative to other traditional radical-triggered reactions in terms of environment, energy, step-economy, health, and safety. The present review mainly focuses on the development of the photocatalytic difluoroalkylation to olefinic moiety using transition-metal complexes, organic dyes as the photocatalyst; and some organic compounds as a medium of photocatalysis.

TEMPO catalyzed oxidative dehydrogenation of hydrazobenzenes to azobenzenes.

A metal-free direct oxidative dehydrogenation approach for the synthesis of azobenzenes from hydrazobenzenes has been developed by using TEMPO as an organocatalyst for the first time. The reaction proceeded in open air under mild reaction conditions. A wide range of hydrazobenzenes readily undergo dehydrogenation to give the corresponding azobenzenes in excellent yields.

Pd(ii)/Zn co-catalyzed chemo-selective hydrogenation of α-methylene-γ-keto carboxylic acids.

An efficient Pd/Zn co-catalyzed chemo-selective hydrogenation of α-methylene-γ-keto carboxylic acids is described. This methodology offers a divergent synthesis of α-methyl-γ-keto carboxylic acids, α-methylcarboxylic acids, and lactones starting from α-methylene-γ-keto carboxylic acids via selective hydrogenation by varying the catalytic conditions avoiding the use of high pressure of hydrogen. The reaction also showed broad substrate tolerance to give the desired products in good to excellent yields.