State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China.
Yunnan Key Laboratory of Natural Medicinal Chemistry, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China.
J Org Chem. 2021 Sep 17;86(18):12762-12771. doi: 10.1021/acs.joc.1c01343. Epub 2021 Aug 31.
A one-step synthesis of diversely substituted pyrazolo[1,5-]pyrimidines from saturated ketones and 3-aminopyrazoles is presented. This transformation involves the in situ formation of α,β-unsaturated ketones via a radical process, followed by [3+3] annulation with 3-aminopyrazoles in one pot. Mechanistic studies have shown that the dual C(sp)-H bond functionalization of inactive ketones is required for the formation of the title compounds. Notably, this dehydrogenative coupling process provides access to a host of functionalized pyrazolo[1,5-]pyrimidines with antitumor potential from commercially available substrates.
本文报道了一种从饱和酮和 3-氨基吡唑出发，一步合成多种取代的吡唑并[1,5-a]嘧啶的方法。该转化通过自由基过程原位形成α,β-不饱和酮，然后在一锅条件下与 3-氨基吡唑进行[3+3]环加成。机理研究表明，标题化合物的形成需要对惰性酮进行双 C(sp)-H 键官能化。值得注意的是，这种脱氢偶联过程为从商业可得的底物中获得具有抗肿瘤潜力的各种功能化吡唑并[1,5-a]嘧啶提供了途径。
