Formal Bimolecular [2 + 2 + 2] Cycloaddition Strategy for the Synthesis of Pyridines: Intramolecular Propargylic Ene Reaction/Aza Diels–Alder Reaction Cascades
作者:Michiko Sasaki、Philip J. Hamzik、Hidaka Ikemoto、Samuel G. Bartko、Rick L. Danheiser
DOI:10.1021/acs.orglett.8b02728
日期:2018.10.5
intramolecular propargylic enereaction in the presence of an azadienophile. Reactions employing ethyl N-(tosyl)iminoacetate furnish an intermediate that undergoes elimination and isomerization upon the addition of DBU. The reaction of the intermediate vinylallene with TsCN leads to the isolation of a 2-sulfonylpyridine that serves as a versatile intermediate undergoing substitution reactions with oxygen and