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Sustainable Synthetic Approach for (Pyrazol-4-ylidene)pyridines By Metal Catalyst-Free Aerobic C(sp²)-C(sp³) Coupling Reactions between 1-Amino-2-imino-pyridines and 1-Aryl-5-pyrazolones.

ABSTRACT: A novel, metal catalyst-free, and efficient method has been developed for the synthesis of (pyrazol-4-ylidene)pyridine derivatives. The process involves dehydrogenative coupling of 1-amino-2-imino-pyridines with 1-aryl-5-pyrazolone derivatives utilizing O₂ as the sole oxidant. The new method benefits from a high atom economy, efficiency, and substrate scope, as well as the simplicity of reaction and product purification procedures.

SUBMITTER: Ibrahim HM

PROVIDER: S-EPMC6682090 | biostudies-literature |

REPOSITORIES: biostudies-literature

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