Five-membered ring systems: pyrroles and benzo analogs

Progress in heterocyclic chemistry, Journal Year: 2023, Volume and Issue: unknown, P. 199 - 250

Published: Jan. 1, 2023

Language: Английский

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Self-Assembly of 4,4′-Linked Dipyrromethanes from Unconventional Reactants─Propargylamines, 2-(Vinyloxy)ethyl Isothiocyanate, and Alkylating Agents under Basic Conditions

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 89(2), P. 864 - 881

Published: Dec. 28, 2023

Self-assembly of 4,4′-linked dipyrromethanes from 2-(vinyloxy)ethyl isothiocyanate, tertiary propargylamines, and alkylating agents has been discovered. The plausible reaction mechanism, the major stages which have confirmed experimentally, includes (1) lithiation propargylamine (with n-BuLi); (2) formation lithium N-[2-(vinyloxy)ethyl]but-2-ynimidothioate (product addition monolithiated to isothiocyanate); (3) isomerization latter in corresponding allenylimidothioate (under action t-BuOK/t-BuOH system); (4) low-temperature (<15 °C) intramolecular cyclization into potassium N-(5-amino-2-thienyl)-N-[2-(vinyloxy)ethyl]amide; (5) base-induced cleavage C–O bond N-[2-(vinyloxy)ethyl] group removal vinyloxide-anion leading acetaldehyde; (6) interaction acetaldehyde with two molecules N-(5-amino-2-thienyl)-N-[2-(vinyloxy)ethyl]amide-anion resulting dithienomethane N-anionic intermediate; (7) recyclization dipyrromethane S-anionic intermediate. Final S-alkylation affords synthetically challenging 4,4′-dipyrromethanes a yield 22–51%. whole process is carried out single synthetic operation very short time (∼10–15 min, excluding alkylation time).

Language: Английский

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Reactions of Acetylenic and Allenic Carbanions with Heterocumulenes: A Straightforward Route to Fundamental Heterocycles

Russian Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 59(10), P. 1676 - 1703

Published: Oct. 1, 2023

Language: Английский

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Acetylenic and allenic carbanions in the reaction with heterocumulenes: a simple way to fundamental heterocycles

Журнал органической химии, Journal Year: 2023, Volume and Issue: 59(10), P. 1319 - 1350

Published: Dec. 15, 2023

Language: Английский

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