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From Propargylic Alcohols to Substituted Thiochromenes: gem-Disubstituent Effect in Intramolecular Alkyne Iodo/hydroarylation.

ABSTRACT: This work describes the 6-endo-dig cyclization of S-aryl propargyl sulfides to afford 2H-thiochromenes. The substitution at the propargylic position plays a crucial role in allowing intramolecular silver-catalyzed alkyne hydroarylation and N-iodosuccinimide-promoted iodoarylation. Additionally, a PTSA-catalyzed thiolation reaction of propargylic alcohols was developed to synthesize the required tertiary S-aryl propargyl ethers. The applicability of merging these two methods is demonstrated by synthesizing the retinoic acid receptor antagonist AGN194310.

SUBMITTER: Velasco N

PROVIDER: S-EPMC8474117 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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From Propargylic Alcohols to Substituted Thiochromenes: gem-Disubstituent Effect in Intramolecular Alkyne Iodo/hydroarylation.

Velasco Noelia N Suárez Anisley A Martínez-Lara Fernando F Fernández-Rodríguez Manuel Ángel MÁ Sanz Roberto R Suárez-Pantiga Samuel S

The Journal of organic chemistry 20210430 10

This work describes the 6-endo-dig cyclization of S-aryl propargyl sulfides to afford 2H-thiochromenes. The substitution at the propargylic position plays a crucial role in allowing intramolecular silver-catalyzed alkyne hydroarylation and N-iodosuccinimide-promoted iodoarylation. Additionally, a PTSA-catalyzed thiolation reaction of propargylic alcohols was developed to synthesize the required tertiary S-aryl propargyl ethers. The applicability of mergi ...[more]

PMID: 33928778

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