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Synthesis of 1-(2-Fluorophenyl)pyrazoles by 1,3-Dipolar Cycloaddition of the Corresponding Sydnones.

ABSTRACT: 3-Arylsydnones bearing fluorine and bromine atoms on the benzene ring were synthesized from N-nitroso-2-fluorophenylglycines and characterized by NMR spectroscopy. These were employed further in synthesis of the corresponding 1-(2-fluorophenyl)pyrazoles by 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate (DMAD) as activated dipolarophile. The sydnones as reaction intermediates were characterized by single crystal X-ray diffraction analysis showing interesting features such as halogen bonding as an important interaction in modeling the crystal structure.

SUBMITTER: Dumitrescu D

PROVIDER: S-EPMC8235238 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Synthesis of 1-(2-Fluorophenyl)pyrazoles by 1,3-Dipolar Cycloaddition of the Corresponding Sydnones.

Dumitrescu Denisa D Shova Sergiu S Draghici Constantin C Popa Marcel Mirel MM Dumitrascu Florea F

Molecules (Basel, Switzerland) 20210617 12

3-Arylsydnones bearing fluorine and bromine atoms on the benzene ring were synthesized from <i>N</i>-nitroso-2-fluorophenylglycines and characterized by NMR spectroscopy. These were employed further in synthesis of the corresponding 1-(2-fluorophenyl)pyrazoles by 1,3-dipolar cycloaddition reaction with dimethyl acetylenedicarboxylate (DMAD) as activated dipolarophile. The sydnones as reaction intermediates were characterized by single crystal X-ray diffraction analysis showing interesting featur ...[more]

PMID: 34204262

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