TfOH-Catalyzed [4 + 1] Annulation of p-Quinone Methides with α-Aryl Diazoacetates: Straightforward Access to Highly Functionalized 2,3-Dihydrobenzofurans

Autor:	Fen-Er Chen, Zuolin Lu, Qing-Chun Zhang, Xiao Xiao, Sha Hu, Miaolin Ke
Rok vydání:	2021
Předmět:	Annulation 010405 organic chemistry Aryl Organic Chemistry Synthon Protonation 010402 general chemistry 01 natural sciences Combinatorial chemistry 0104 chemical sciences Quinone chemistry.chemical_compound chemistry Organocatalysis Intramolecular force Michael reaction
Zdroj:	The Journal of Organic Chemistry. 86:7625-7635
ISSN:	1520-6904 0022-3263
DOI:	10.1021/acs.joc.1c00672
Popis:	We have developed a methodology for the greatly efficient construction of significant 2,3-dihydrobenzofuran scaffolds bearing a quaternary carbon center at the C2 position by means of [4 + 1] annulation reactions between p-quinone methides and α-aryl diazoacetates as C1 synthons through organocatalysis by readily accessible TfOH catalyst under mild and transition metal-free conditions. This metal-free protocol furnishes an operationally simple and swift process for the free assembly of diverse highly functionalized 2,3-dihydrobenzofurans and also features broad substrate scope, excellent functional group compatibility, and environmental friendliness. Mechanistic investigation suggested that the reaction undergoes a rapid cascade protonation/intermolecular Michael addition/intramolecular substitution process.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::5abeddf4b8dc56cd9fdfbfb82b650a6a https://doi.org/10.1021/acs.joc.1c00672 Zobrazit plný text záznamu