Highly Efficient Ruthenium-Catalyzed N-Formylation of Amines with H2 and CO2†
We acknowledge the National Natural Science Foundation of China (grant nos. 91127041, 20421091, 21472215), a special fund from the Chinese Academy of Sciences (XDA07040404), and the Science and Technology Commission of Shanghai Municipality for financial support of this work.
Graphical Abstract
Just a pinch: CO2 is efficiently hydrogenated for N-formylation of various amines using ruthenium-pincer catalysts, thus affording the corresponding formamides with extremely high turnover numbers (TONs). The catalyst was readily reused for 12 runs without significant loss of activity in N,N-dimethylformamide production, thus demonstrating potential for practical utilization of this cost-effective process.
Abstract
A highly efficient catalyst system based on ruthenium-pincer-type complexes has been discovered for N-formylation of various amines with CO2 and H2, thus affording the corresponding formamides with excellent productivity (turnover numbers of up to 1 940 000 in a single batch) and selectivity. Using a simple catalyst recycling protocol, the catalyst was reused for 12 runs in N,N-dimethylformamide production without significant loss of activity, thus demonstrating the potential for practical utilization of this cost-effective process. A one-pot two-step procedure for hydrogenation of CO2 to methanol via the intermediacy of formamide formation has also been developed.
