Wang Wenqing, Tan Gengwen, Feng Rui, Fang Yong, Chen Chao, Ruan Huapeng, Zhao Yue, Wang Xinping
College of Chemistry and Material Science, Key Laboratory of Functional Molecular Solids, Ministry of Education, Anhui Laboratory of Molecule-Based Materials, Anhui Normal University, Wuhu, Anhui 241002, China and State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Chem Commun (Camb). 2020 Mar 17;56(22):3285-3288. doi: 10.1039/c9cc07382e.
Azo radical anion 1˙- and dianion 12- have been isolated by one- and two-electron reduction of the azo compound 1 (ArNNAr, Ar = 4-CN-2,6-iPr2-C6H2) with alkali metals, respectively. The reduced species have been characterized by single-crystal X-ray analysis, EPR, UV and FT-IR spectroscopy, as well as SQUID measurements. The filling of one and two electrons in the π* orbital of the N-N double bond of 1 leads to a half-double N-N bond in 1˙- and a single N-N bond in 12-. The uncoordinated nature of these reduced species enables them to activate CO2. The exposure of 1˙- solution to CO2 led to the formation of oxalate anion C2O42-, while that of 12- solution to CO2 afforded the hydrazine dicarboxylate dianion [1-2CO2]2-, which reversibly dissociated back to 1 and CO2 upon oxidation.
