Iron Nitrate-Mediated Selective Synthesis of 3-Acyl-1,2,4-oxadiazoles from Alkynes and Nitriles: The Dual Roles of Iron Nitrate

Qilong Bian, Cunluo Wu, Jiangpei Yuan, Zuodong Shi, Tao Ding, Yongwei Huang, Hao Xu* and Yuanqing Xu*

*Institute of Functional Organic Molecular Engineering, College of Chemistry and Chemical Engineering, Henan University, Kaifeng 475004, China, Email: xuhaohenu.edu.cn, 18937822307163.com

Q. Bian, C. Wu, J. Yuan, Z. Shi, T. Ding, Y. Huang, H. Xu, Y. Xu, J. Org. Chem., 2020, 85, 4058-4066.

DOI: 10.1021/acs.joc.9b03070

---

Abstract

Iron(III) nitrate mediates a selective synthesis of 3-acyl-1,2,4-oxadiazoles from alkynes and nitriles. A nitration of alkynes leads to α-nitroketones, dehydration of α-nitroketones provides the nitrile oxides, and a subsequent 1,3-dipolar cycloaddition of nitrile oxides with nitriles produces 3-acyl-1,2,4-oxadiazoles.

see article for more examples

proposed mechanism

---

---

Iron-Mediated Synthesis of Isoxazoles from Alkynes: Using Iron(III) Nitrate as a Nitration and Cyclization Reagent

Z. Lai, Z. Li, Y. Liu, P. Yang, X. Fang, W. Zhang, B. Liu, H. Chang, H. Xu, Y. Xu, J. Org. Chem., 2018, 83, 145-153.

---

Key Words

1,2,4-oxadiazoles, terminal alkynes, 1,3-dipolar cycloaddition

---

ID: J42-Y2020