Regioselective, Lewis Acid-Catalyzed Ring-Openings of 2,3-Aziridyl Alcohols with Azoles

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 25, 2025

Methods for regioselective ring-opening reactions of N-sulfonyl-protected aziridyl alcohols with azole nucleophiles have been developed. Several classes azoles, including indazole, substituted pyrazole, benzotriazole, and tetrazole, employed as reaction partners, giving rise to C3-selective opening >3:1 N-selectivity. BF3•OEt2 is the optimal catalyst most substrate combinations, although examples where diphenylborinic acid (Ph2BOH) provides higher yields, or proceed efficiently without a catalyst, are also described. Computational modeling BF3•OEt2-catalyzed consistent observed regiochemical outcome. The calculated transition state appears be stabilized by an unconventional OH···FB hydrogen-bonding interaction.

Язык: Английский

B/Cu Synergistic Catalysis for the Asymmetric Mannich Reaction between β,γ-Alkynyl-α-ketimino Esters and Ortho-Hydroxy Aryl Ketones

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Июнь 2, 2025

Herein, we present a B/Cu-catalyzed asymmetric Mannich reaction, utilizing β,γ-alkynyl-α-ketimino esters and ortho-hydroxy aryl ketones. The reaction initiates with the activation of ketones via borinic acid to form tetracoordinated enol boronate complex, followed by chiral Cu complex-assisted an electrophilic ketimino ester. also works alkyl-chained ketones, producing adducts moderate good diastereoselectivity. practical applicability is evidenced gram-scale subsequent elaboration adduct.

Язык: Английский

Iodide Enhances the Production of Pseurotin D over Pseurotin A by Inverting the Preference for the S_N2 versus the S_N2′ Product in the Final Nonenzymatic Step

Journal of Natural Products, Год журнала: 2024, Номер unknown

Опубликована: Дек. 23, 2024

Nonenzymatic reactions, though critical in natural product biosynthesis, are significantly challenging to control. Adding 3% NaI the culture medium of

Язык: Английский