Collaborative Activation of Trifluoroacetyl Diazoester by a Lewis Acid and Base for the Synthesis of Polysubstituted 4‑Trifluoromethylpyrazoles
datasetposted on 22.06.2020, 10:43 by Zheng Fang, Hongshan Yin, Lu Lin, Shunli Wen, Lili Xie, Yangjie Huang, Zhiqiang Weng
A Lewis acid- and base-co-mediated cyclization of trifluoroacetyl diazoester and ketones is developed. Cooperative functioning of the Lewis acid and Lewis base with trifluoroacetyl diazoester results in increased electrophilicity of terminal nitrogen atoms. The reaction affords polysubstituted 4-trifluoromethyl pyrazoles in moderate to excellent yields.