Photocatalytic dehydrogenative C-C coupling of acetonitrile to succinonitrile

Xian Zhou; Xiaofeng Gao; Mingjie Liu; Zirui Gao; Xuetao Qin; Wenhao Xu; Shitong Ye; Wenhua Zhou; Haoan Fan; Jing Li; Shurui Fan; Lei Yang; Jie Fu; Dequan Xiao; Lili Lin; Ding Ma; Siyu Yao

doi:10.1038/s41467-022-32137-y

Photocatalytic dehydrogenative C-C coupling of acetonitrile to succinonitrile

Nat Commun. 2022 Jul 28;13(1):4379. doi: 10.1038/s41467-022-32137-y.

Authors

Xian Zhou¹, Xiaofeng Gao², Mingjie Liu¹, Zirui Gao², Xuetao Qin², Wenhao Xu¹, Shitong Ye¹, Wenhua Zhou¹, Haoan Fan¹, Jing Li¹, Shurui Fan³, Lei Yang⁴, Jie Fu¹, Dequan Xiao⁵, Lili Lin⁶, Ding Ma⁷, Siyu Yao^{8

9}

Affiliations

¹ Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China.
² Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, Peking University, Beijing, China.
³ Institute of Industrial Catalysis, State Key Laboratory of Green Chemistry Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, Zhejiang, China.
⁴ Zhejiang Henglan Science and Technology Co. Ltd, Hangzhou, 310027, China.
⁵ Center for Integrative Materials Discovery, Department of Chemistry and Chemical and Biomedical Engineering, University of New Haven, West Haven, CT, 06516, USA.
⁶ Institute of Industrial Catalysis, State Key Laboratory of Green Chemistry Synthesis Technology, College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, Zhejiang, China. linll@zjut.edu.cn.
⁷ Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, Peking University, Beijing, China. dma@pku.edu.cn.
⁸ Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou, 310027, China. yaosiyu@zju.edu.cn.
⁹ Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, Peking University, Beijing, China. yaosiyu@zju.edu.cn.

Abstract

The coupling of acetonitrile into succinonitrile, an important terminal dinitrile for value-added nylon production, via a dehydrogenative route is highly attractive, as it combines the valuable chemical synthesis with the production of green hydrogen energy. Here, we demonstrate that it is possible to achieve a highly selective light driven dehydrogenative coupling of acetonitrile molecules to synthesize succinonitrile using anatase TiO₂ based photocatalysts in aqueous medium under mild conditions. Under optimized conditions, the formation rate of succinonitrile reaches 6.55 mmol/(g_cat*h), with over 97.5% selectivity to target product. Mechanism studies reveal that water acts as cocatalyst in the reaction. The excited hole of anatase semiconductor oxidizes water forming hydroxyl radical, which subsequently assists the cleavage of sp³ C-H bond of acetonitrile to generate ·CH₂CN radical for further C-C coupling. The synergy between TiO₂ and Pt cocatalyst is important to enhance the succinonitrile selectivity and prevent undesirable over-oxidation and hydrolysis. This work offers an alternative route to prepare succinonitrile based on renewable energy under mild conditions and avoid the use of toxic reagents and stoichiometric oxidative radical initiators.