95994-33-5Relevant academic research and scientific papers
NHC-catalyzed regiodivergent syntheses of difunctionalized 3-pyrazolidinones from α-bromoenal and monosubstituted hydrazine
Yu, Chenxia,Shen, Shide,Jiang, Ligen,Li, Jing,Lu, Yumiao,Li, Tuanjie,Yao, Changsheng
supporting information, p. 9149 - 9155 (2017/11/14)
A formal [3 + 2] annulation of α-bromoenal with monosubstituted hydrazine could give 1,5 or 2,5-difunctionalized 3-pyrazolidinone regiodivergently by tuning the structure of the N-Heterocyclic Carbene (NHC) catalyst. Moderate to high yields, mild reaction conditions, good regioselectivity and potential biological significance of the final product have made this protocol attractive for the assembly of 3-pyrazolidinone.
DMF-catalyzed direct and regioselective C-H functionalization: Electrophilic/nucleophilic 4-halogenation of 3-oxypyrazoles
Liu, Yuanyuan,He, Guangke,Chen, Kai,Jin, Yin,Li, Yufeng,Zhu, Hongjun
supporting information; experimental part, p. 5323 - 5330 (2011/11/13)
A novel, straightforward, and highly regioselective 4-chlorination of 3-oxypyrazole derivatives in boiling thionyl chloride (SOCl2) in the presence of catalytic N,N-dimethylformamide (DMF) has been developed. This reaction likely proceeds through a DMF-catalyzed electrophilic/nucleophilic chlorination mechanism and involves electrophilic attack by SOCl2 and nucleophilic substitution by Cl- as the key steps. Based on this mechanism, the corresponding 4-bromination and 4-iodination of 3-oxypyrazoles have also been achieved in good yield by adding Br- and I -, respectively, to the reaction system. This halogenation method enables quick access to many original 4-halo-3-oxypyrazole series. A novel DMF-catalyzed electrophilic/nucleophilic 4-halogenation of 3-oxypyrazole derivatives has been developed. This halogenation procedure provides quick access to many novel 4-halo-3-oxypyrazole series.
Synthesis, crystal structure, and fungicidal activity of novel 1,5-Diaryl-1H-pyrazol-3-oxyacetate derivatives
Liu, Yuanyuan,Shi, Hong,Li, Yufeng,Zhu, Hongjun
experimental part, p. 897 - 902 (2010/10/18)
A series of ethyl 2-(1,5-diaryl-1H-pyrazol-3-yloxy)acetate derivatives (5a-5i) have been efficiently synthesized by the reaction of 1,5-diaryl-1H-pyrazol-3-ols (4a-4i) with ethyl 2-bromoacetate. The structures of the newly synthesized compounds were characterized by 1H NMR spectra and elemental analysis, and the crystal structure of the compound ethyl 2-(5-(4-chlorophenyl)-1-phenyl-1H-pyrazol-3-yloxy)acetate (5c) was determined by single crystal X-ray diffraction analysis. The compound 5c belongs to triclinic system with space group P(-1), a = 5.8170(12) A, b = 11.804(2) A, c = 12.783(2) A, α = 83.89(2)°, β = 89.24(3)°, γ = 89.73(3)°, Formula weight: 356.80, Triclinic V = 872.7(3) A3, Dc = 1.358 mg/m3, Z = 2, F (000) = 372. Bioassay results indicated that the compound ethyl 2-(5-(4-fluorophenyl)-1- phenyl-1H-pyrazol-3-yloxy)acetate (5d) exhibited moderate inhibitory activity against Gibberella zeae at the dosage of 10 μg/mL.
