Formal [3 + 3] Cycloaddition Reactions between Electron-Deficient Cyclopropenes and Hydrazones: A Route to Alkyl 1,4,5,6-Tetrahydropyridazine-3-carboxylates
作者:Hengrui Huo、Runa A、Yuefa Gong
DOI:10.1021/acs.joc.8b03105
日期:2019.2.15
regioselective fashion and gave alkyl 1,4,5,6-tetrahydropyridazine-3-carboxylates in high yields under mild basic conditions. Treatment of the annulation products with DDQ leads to the formation of functionalized pyridazine-3-carboxylates, analogues of nicotinicacidester.
A metal‐free approach for the synthesis of 5‐trifluoromethyl‐1,2,4‐triazoles from trifluoroacetimidoyl chlorides and hydrazones has been achieved under aerobic oxidative conditions. The reaction proceeds through a cascade base‐promoted intermolecular C−N bond formation and iodine‐mediated intramolecular C−N bond oxidative coupling sequence. The protocol features broad substrate scope and can be scaled
An operationally simple EosinYcatalyzed sulfenylation of hydrazones has been realized to afford a range of thioethers under visible light. The methodology provides high yields of thioethers under ambient conditions employing readily available and inexpensive starting materials. The reaction has broad substrate scope and is compatible with various functional groups.