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A New Method for the Synthesis of 3-Thiocyanatopyrazolo[1,5-a]pyrimidines.

ABSTRACT: In this article, we demonstrate how an original effective "metal-free" and "chromatography-free" route for the synthesis of 3-thiocyanatopyrazolo[1,5-a]pyrimidines has been developed. It is based on electrooxidative (anodic) C-H thiocyanation of 5-aminopyrazoles by thiocyanate ion leading to 4-thiocyanato-5-aminopyrazoles (stage 1, yields up to 87%) following by their chemical condensation with 1,3-dicarbonyl compounds or their derivatives (stage 2, yields up to 96%). This method is equally effective for the synthesis of 3-thiocyanatopyrazolo[1,5-a]pyrimidines, both without substituents and with various donor (acceptor) substituents in the pyrimidine ring.

SUBMITTER: Kokorekin VA

PROVIDER: S-EPMC7570695 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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A New Method for the Synthesis of 3-Thiocyanatopyrazolo[1,5-a]pyrimidines.

Kokorekin Vladimir A VA Neverov Sergey V SV Kuzina Vera N VN Petrosyan Vladimir A VA

Molecules (Basel, Switzerland) 20200911 18

In this article, we demonstrate how an original effective "metal-free" and "chromatography-free" route for the synthesis of 3-thiocyanatopyrazolo[1,5-a]pyrimidines has been developed. It is based on electrooxidative (anodic) C-H thiocyanation of 5-aminopyrazoles by thiocyanate ion leading to 4-thiocyanato-5-aminopyrazoles (stage 1, yields up to 87%) following by their chemical condensation with 1,3-dicarbonyl compounds or their derivatives (stage 2, yields up to 96%). This method is equal ...[more]

PMID: 32933044

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