Intramolecular (4+3) Cycloadditions of Oxidopyridinium Ions: Towards Daphnicyclidin A

Autor:	Jianzhuo Tu, Rawshan A. Ripa, Steven P. Kelley, Michael Harmata
Rok vydání:	2022
Předmět:	Ions Alkaloids Cycloaddition Reaction Organic Chemistry General Chemistry Carbon Catalysis
Zdroj:	Chemistry – A European Journal. 28
ISSN:	1521-3765 0947-6539
Popis:	N-alkylation of 5-hydroxynicotinic acid esters with electrophiles containing diene functionality produces salts that undergo intramolecular (4+3) cycloaddition reactions upon heating in the presence of base. Initial studies used a three-carbon tether to join the pyridinium ion and diene, revealing some aspects of the inherent selectivity of the reaction with such substrates. Much more challenging was the synthesis of related species possessing only a two-carbon tether. Nevertheless, the cycloaddition of such compounds was successful, leading directly to the ABC ring system of the alkaloid daphnicyclidin A.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::48b1cb964bf6b9d2387792274f385b37 https://doi.org/10.1002/chem.202200370 Zobrazit plný text záznamu Plný text