Synergistic cesium carbonate-promoted dehydration of ketonitrones: stereoselective synthesis of indenyl-2-azadienes
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Updated: Jun 17, 2026

Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
Meng-Xia Shen1,2, Shen-Yu Ren2, Yi-Zhuo Liu2
1Key Laboratory of Theoretical Organic Chemistry and Functional Molecule of the Ministry of Education, School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China. liuyilinhn@126.com.
Abstract:
A strategy for N-O bond cleavage of ketonitrones promoted by cesium carbonate has been developed, enabling access to indenyl-2-azadienes via a dehydration process. Both cyclic indanone-derived nitrones and acyclic ketonitrones underwent dehydration in a Cs2CO3/toluene system to afford 2-azadienes in high yields with excellent selectivity. Control experiments indicated that the synergistic cesium ion-directed deprotonation of the α-hydrogen of the ketonitrone generating a carbanion intermediate is the key step in the dehydration process. Moreover, 1-aminoindane, a privileged scaffold present in numerous pharmaceutical agents, is readily accessible through the selective reduction of 2-azadiene.
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