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An efficient metal-free and catalyst-free C-S/C-O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides.

ABSTRACT: An operationally simple and metal-free approach is described for the synthesis of pyrazole-tethered thioamide and amide conjugates. The thioamides were generated by employing a three-component reaction of diverse pyrazole C-3/4/5 carbaldehydes, secondary amines, and elemental sulfur in a single synthetic operation. The advantages of this developed protocol refer to the broad substrate scope, metal-free and easy to perform reaction conditions. Moreover, the pyrazole C-3/5-linked amide conjugates were also synthesized via an oxidative amination of pyrazole carbaldehydes and 2-aminopyridines using hydrogen peroxide as an oxidant.

SUBMITTER: Sharma S

PROVIDER: S-EPMC9989676 | biostudies-literature | 2023

REPOSITORIES: biostudies-literature

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An efficient metal-free and catalyst-free C-S/C-O bond-formation strategy: synthesis of pyrazole-conjugated thioamides and amides.

Sharma Shubham S Singh Dharmender D Kumar Sunit S Vaishali Jamra Rahul R Banyal Naveen N Deepika Malakar Chandi C CC Singh Virender V

Beilstein journal of organic chemistry 20230302

An operationally simple and metal-free approach is described for the synthesis of pyrazole-tethered thioamide and amide conjugates. The thioamides were generated by employing a three-component reaction of diverse pyrazole C-3/4/5 carbaldehydes, secondary amines, and elemental sulfur in a single synthetic operation. The advantages of this developed protocol refer to the broad substrate scope, metal-free and easy to perform reaction conditions. Moreover, the pyrazole C-3/5-linked amide conjugates ...[more]

PMID: 36895429

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