219986-66-0

Upstream product

• 937-31-5 (4-Nitrophenyl)acetylene 
• 2236129-81-8 trifluoroacetaldehyde N-triftosylhydrazone 
• 425391-02-2 (p-nitrobenzoyl)trifluoroacetonate 
• 709-63-7 1-(4-trifluoromethylphenyl)ethanone 
• 100-19-6 (4-nitrophenyl)ethanone 
• 371-67-5 2,2,2-trifluorodiazoethane 
• 35999-53-2 4,4,4-trifluoro-1-(4-nitrophenyl)butane-1,3-dione 
• 51144-19-5 (3-methyl-quinoxalin-2-yl)-hydrazine 
• 1514-82-5 2-bromo-3,3,3-trifluoropropene 
• 555-16-8 4-nitrobenzaldehdye 

Downstream Products

• 1367825-81-7 5-(4-nitrophenyl)-1H-pyrazole-3-carbonitrile 

Relevant academic research and scientific papers

Cycloaddition of Trifluoroacetaldehyde N-Triftosylhydrazone (TFHZ-Tfs) with Alkynes for Synthesizing 3-Trifluoromethylpyrazoles

A transition-metal-free [3 + 2] cycloaddition between trifluoroacetaldehyde N-triftosylhydrazone (TFHZ-Tfs) and alkynes is reported. This protocol provides an operationally simple and general method for the synthesis of diverse 3-trifluoromethylpyrazoles in good to excellent yields with broad substrate scope, including aryl, heteroaryl, and alkyl terminal alkynes, and electron-deficient internal alkynes. The synthetic potential of this method was further demonstrated by the synthesis of an antiarthritic drug Celecoxib in multigram scale.

Regioselective Synthesis of 3-Trifluoromethylpyrazole by Coupling of Aldehydes, Sulfonyl Hydrazides, and 2-Bromo-3,3,3-trifluoropropene

A general and practical strategy for 3-trifluoromethylpyrazole synthesis is reported that occurs by the three-component coupling of environmentally friendly and large-tonnage industrial feedstock 2-bromo-3,3,3-trifluoropropene (BTP), aldehydes, and sulfonyl hydrazides. This highly regioselective three-component reaction is metal-free, catalyst-free, and operationally simple and features mild conditions, a broad substrate scope, high yields, and valuable functional group tolerance. Remarkably, the reactions could be performed on a 100 mmol scale and smoothly afforded the key intermediates for the synthesis of celecoxib, mavacoxib, SC-560, and AS-136A. Preliminary mechanism studies indicated that a 1,3-hydrogen atom transfer process was involved in this transformation.

Highly tunable fluorinated trispyrazolylborates [HB(3-CF3-5-{4-RPh}pz)3]- (R = NO2, CF3, Cl, F, H, OMe and NMe2) and their copper(i) complexes

The ethene and carbon monoxide adducts of copper(i) with seven trispyrazolylborate ligands ([HB(3-CF3-5-{4-RPh}pz)3]-; R = NO2 (4a), CF3 (4b), Cl (4c), F (4d), H (4e), OMe (4f) and NMe2 (4g)) were synthesized and characterized. The ligands were synthesized from their corresponding pyrazoles and sodium tetrahydridoborate and were obtained as solvent adducts of their sodium salts after workup. When the pyrazole with the most electron-withdrawing substituent (R = NO2) is used the asymmetric ligand [HB(3-CF3-5-{4-NO2Ph}pz)2(3-{4-NO2Ph}-5-CF3pz)]- (4a′) is formed as the major product. Copper(i) complexes with ethene or CO as a co-ligand were prepared in good yields and were structurally characterized using 1H NMR, 13C NMR and infrared spectroscopy. Single crystal X-ray crystallography analyses revealed the structures of Na4a′, Na4b, four copper ethene complexes and four copper carbonyl complexes. The structures of the copper(i) complexes show CuI ions in pseudo-tetrahedral coordination environments consisting of three nitrogen atoms of the trispyrazolylborate ligand and the carbonyl or η2-coordinated ethene ligands, with nearly identical coordination environments around the CuI ion. The compound [Na(4a′)(H2O)]n crystallizes as one-dimensional chains with intermolecular Na...O2N interactions. The sodium ions were found in severely distorted octahedral geometries with three nitrogen atoms from the trispyrazolylborate ligand, one aqua ligand and two oxygen atoms from the nitro group of an adjacent molecule. The compound [Na2(4b)2(μ-H2O)2] crystallizes as a centrosymmetric water-bridged dimer: two five-coordinate square-pyramidal sodium ions each are coordinated facially by three nitrogen atoms from a trispyrazolylborate ligand and two bridging water ligands. Below the base of the pyramidal structure one intermolecular and two intramolecular Na...F short contacts are present. The 1H and 13C NMR spectra of the copper-ethene complexes show signals for the ethene ligands in the range of 4.84-4.96 ppm and 84.9-86.8 ppm respectively. The infrared spectra of the carbonyl complexes show CO stretching frequencies in the range of 2096-2120 cm-1. Both the NMR signals for the ethene ligands and infrared signals for the carbonyl ligands were found to show good correlations with the Hammett σp parameters of the substituents on the phenyl rings of the ligands.

Silver-mediated cycloaddition of alkynes with CF3CHN 2: Highly regioselective synthesis of 3-trifluoromethylpyrazoles

Silver screen: The title reaction provides a convenient and efficient method for the construction of 5-substituted 3-trifluoromethylpyrazoles under mild reaction conditions. By using this protocol, the marketed drug Celecoxib (antiarthritic) could be easily synthesized (see scheme; DMF=N,N- dimethylformamide). Copyright

Synthesis and anti-microbial activity of some new fluorinated 1H-pyrazoles

Several new trifluoromethyl-1H-pyrazoles were prepared by reaction of hydrazine monohydrate with 1,3-diketones. Their structures were confirmed by elemental analysis, IR, 1H NMR and EI-MS spectroscopy. The anti-microbial activities of the newly synthesized compounds were examined by disc diffusion method against Escherichia coli, Staphylococcus aureus, Pyricularia oryzae and Rhizoctnia solani. All the trifluoromethyl-1H-pyrazoles exhibited a certain degree of anti-bacterial and anti-fungal activities.

Some novel observations on the reaction of 2-hydrazino-3-methylquinoxaline with trifluoromethyl-β-diketones

The reaction of 2-hydrazino-3-methylquinoxaline 1 with trifluoromethyl-β-diketones 2 not only yields the expected 5-trifluoromethyl-5-hydroxy-Δ2-pyrazolines 3a-3f and/or 3-trifluoromethylpyrazoles 4c-4f but also the unexpected products 1,2,4-tr