A highly efficient ruthenium pincer-catalyzed Guerbet-type process for the production of biofuel from ethanol has been developed. It produces the highest conversion of ethanol (73.4%, 0.02 mol% catalyst) for a Guerbet-type reaction, including significant amounts of C4 (35.8% yield), C6 (28.2% yield), and C8 (9.4% yield) alcohols. Catalyst loadings as low as 0.001 mol% can be used, leading to a record turnover number of 18 209. Mechanistic studies reveal the likely active ruthenium species and the main deactivation process.

Hydrogen has long been regarded as an ideal alternative clean energy vector to overcome the drawbacks of fossil technology. However, the direct utilization of hydrogen is challenging, due to low volumetric energy density of hydrogen gas and potential safety issues. Herein, we report an efficient and reversible liquid to liquid organic hydrogen carrier system based on inexpensive, readily available and renewable ethylene glycol. This hydrogen storage system enables the efficient and reversible loading and discharge of hydrogen using a ruthenium pincer complex, with a theoretical hydrogen storage capacity of 6.5 wt%.

A novel and efficient Rh/O2 catalytic system has been developed and shown to catalyze highly efficient oxidative C-H activation/annulation reactions, producing a broad range of isoquinolinium salts with high turnover numbers (up to 740). Mechanistic studies provided strong evidence of facile oxidation of Rh(I) to Rh(III) by molecular oxygen facilitated by acid.

An efficient and conceptually new method for oxidative amination of azoles with tertiary amines via copper-catalyzed C-H and C-N bond activation has been developed. This protocol can be performed in the absence of external base and only requires atmospheric oxygen as oxidant. The catalyst system is very simple and efficient, which opens a new way for using tertiary amines as nitrogen group sources for C-N bond formation reactions.