Hydrogenation of Alkynes and Olefins Catalyzed by Quaternary Ammonium Salts
Qi Guo1, Guoli Shen1, Guangfu Lu1
1Yunnan Key Laboratory of Chiral Functional Substance Research and Application, School of Chemistry & Environment, Yunnan Minzu University, 2929 Yuehua road, Kunming, 650500, China.
Abstract:
Catalytic hydrogenation of unsaturated hydrocarbons to alkenes and alkanes using molecular hydrogen is one of the most fundamental transformations in organic synthesis. While methodologies involving transition metals as catalysts in homogeneous and heterogeneous processes have been well developed, metal-free catalytic hydrogenation offers an ideal approach for future chemistry. Herein, the common and inexpensive quaternary ammonium salts are first introduced as catalysts in the catalytic hydrogenation system for the transformations from alkynes or olefins into the corresponding olefins or alkanes. Interestingly, the hydrogenation process of alkynes can be controlled to selectively produce alkenes or alkanes under different conditions. Moreover, the possible mechanism is discussed in new insights into the catalytic behavior of quaternary ammonium salts.
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