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Three-component synthesis of C2F5-substituted pyrazoles from C2F5CH2NH2·HCl, NaNO2 and electron-deficient alkynes.

ABSTRACT: A one-pot reaction between C2F5CH2NH2·HCl, NaNO2 and electron-deficient alkynes gives C2F5-substituted pyrazoles in excellent yields. The transformation smoothly proceeds in dichloromethane/water, tolerates the presence of air, and requires no purification of products by column chromatography. Mechanistically, C2F5CH2NH2·HCl and NaNO2 react first in water to generate C2F5CHN2, that participates in a [3 + 2] cycloaddition with electron-deficient alkynes in dichloromethane.

SUBMITTER: Mykhailiuk PK

PROVIDER: S-EPMC4311722 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Three-component synthesis of C2F5-substituted pyrazoles from C2F5CH2NH2·HCl, NaNO2 and electron-deficient alkynes.

Mykhailiuk Pavel K PK

Beilstein journal of organic chemistry 20150106

A one-pot reaction between C2F5CH2NH2·HCl, NaNO2 and electron-deficient alkynes gives C2F5-substituted pyrazoles in excellent yields. The transformation smoothly proceeds in dichloromethane/water, tolerates the presence of air, and requires no purification of products by column chromatography. Mechanistically, C2F5CH2NH2·HCl and NaNO2 react first in water to generate C2F5CHN2, that participates in a [3 + 2] cycloaddition with electron-deficient alkynes in dichloromethane. ...[more]

PMID: 25670987

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