Synthesis 2022; 54(02): 439-450
DOI: 10.1055/s-0040-1719837
paper

Synthesis of Methylene-Bridged Trifluoromethyl Azoles Using 5-(1,2,3-Triazol-1-yl)enones

a   Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
b   Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany
,
Estefania C. Aquino
a   Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
,
Tuvshinjargal Budragchaa
b   Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany
,
Ludger A. Wessjohann
b   Department of Bioorganic Chemistry, Leibniz-Institute of Plant Biochemistry, Weinberg 3, 06120 Halle (Saale), Germany
,
Helio G. Bonacorso
a   Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
,
Marcos A. P. Martins
a   Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
,
Nilo Zanatta
a   Núcleo de Química de Heterociclos (NUQUIMHE), Departamento de Química, Universidade Federal de Santa Maria, 97105-900, Santa Maria, RS, Brazil
› Institutsangaben
The authors are grateful for the financial support from the Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS) (FAPERGS/CNPq – PRONEX, grant no. 16/2551-0000477-3) and CNPq (grant no. 407898/2018-2), as well as the fellowships from Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES (M.M.; E.C.A.), Deutscher Akademischer Austauschdienst – DAAD (M.M. program no. 57507869, grant no. 91793237) and Conselho Nacional de Desenvolvimento Científico e Tecnológico – CNPq (H.G.B.; M.A.P.M; N.Z). T.B. and L.A.W. are grateful for funding supported by the Federal Ministry for Education and Research (BMBF, TV-03ZZ0808C, Chemo-/Enzymatic Profile Adaptation, Project DrugBioTune, Zwanzig20 – Partnerschaft für Innovation).


Abstract

A protocol for synthesizing triazole-containing pyrazolines and pyrazoles selectively using trifluoromethylated 5-(1,2,3-triazol-1-yl)enones as starting materials, is reported. The selectivity of the reaction was controlled by the nature of the hydrazine or derivative used: free hydrazines furnished the 1,5-regiosiomer exclusively in yields up to 98%, whereas protected hydrazines provided the 1,3-regioisomer in yields up to 77%. To demonstrate the synthetic versatility of the triazole-based enone, reactions with other unsymmetrical dinucleophiles (hydroxylamine hydrochloride and S-methyl isothiourea sulfates) allowed the selective preparation of triazole-containing isoxazoline and pyrimidine rings.

Supporting Information



Publikationsverlauf

Eingereicht: 06. August 2021

Angenommen nach Revision: 25. August 2021

Artikel online veröffentlicht:
06. Oktober 2021

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