Department of Chemistry , Yale University , 225 Prospect Street , New Haven , Connecticut 06520 , United States.
Org Lett. 2020 Feb 7;22(3):1217-1221. doi: 10.1021/acs.orglett.0c00186. Epub 2020 Jan 24.
Hydrazones readily synthesized from -aminopyrroles or -aminoazoles and aldehydes undergo Rh(III)-catalyzed dual C-H activation and coupling with aryl- and alkyl-substituted alkynes to give pyrrolopyridazines or azolopyridazines, respectively. This transformation represents a rare example of hydrazoyl C-H activation and proceeds without heteroatom functionality to direct C-H activation. Hydrazones derived from aromatic, alkenyl, and aliphatic aldehydes were effective inputs, and tethering the alkyne to the hydrazone enabled annulations to more complex, tricyclic products.
腙类化合物可由β-氨基吡咯或β-氨基唑与醛类化合物快速合成，在 Rh(III)催化下发生双重 C-H 键活化，并与取代的芳基和烷基炔烃偶联，分别生成吡咯并吡啶嗪或唑并吡啶嗪。该转化是肼基 C-H 键活化的罕见实例，且无需杂原子官能团来导向 C-H 键活化。来自芳香醛、烯基醛和脂肪醛的腙类化合物都是有效的反应物，而将炔烃与腙键连接起来则可以使环化反应生成更复杂的三环产物。
