6833-82-5Relevant academic research and scientific papers
Cycloaddition of Trifluoroacetaldehyde N-Triftosylhydrazone (TFHZ-Tfs) with Alkynes for Synthesizing 3-Trifluoromethylpyrazoles
Wang, Hongwei,Ning, Yongquan,Sun, Yue,Sivaguru, Paramasivam,Bi, Xihe
supporting information, p. 2012 - 2016 (2020/03/04)
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.
SUBSTITUTED PYRAZOLOPYRIMIDINES AND SUBSTITUTED PURINES AND THEIR USE AS UBIQUITIN-SPECIFIC-PROCESSING PROTEASE 1 (USP1) INHIBITORS
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Paragraph 0569, (2020/07/14)
The present disclosure provides compounds having Formula I: and the pharmaceutically acceptable salts and solvates thereof, wherein X1, X2, X11, X12, R1, R3, R5, R5', R6, and R7 are defined as set forth in the specification. The present disclosure is also directed to the use of compounds of Formula I to inhibit a USP1 protein and/or to treat a disorder responsive to the inhibition of USP1 proteins and USP1 activity. Compounds of the present disclosure are especially useful for treating cancer.
Preparation methods for pyrazole compound
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Paragraph 0064; 0064; 0066, (2017/08/30)
The invention discloses preparation methods for a pyrazole compound. The preparation methods include a method A and a method B. The method A comprises a step of subjecting a compound as shown in a formula (II-A) which is described in the specification and a compound as shown in a formula (III) which is described in the specification to a cyclization reaction in a solvent so as to obtain a compound as shown in a formula (I) which is described in the specification. The method B comprises a step of subjecting a compound as shown in a formula (II-B) which is described in the specification and the compound as shown in the formula (III) which is described in the specification to a cyclization reaction in a solvent so as to obtain the compound as shown in the formula (I) which is described in the specification. The preparation methods use cheap and easily available raw materials, are low in production cost, mild in reaction conditions, simple to operate, high in yield and purity of the target compound, green and environment-friendly, and more suitable for industrial production.
A Unified Continuous Flow Assembly-Line Synthesis of Highly Substituted Pyrazoles and Pyrazolines
Britton, Joshua,Jamison, Timothy F.
supporting information, p. 8823 - 8827 (2017/07/17)
A rapid and modular continuous flow synthesis of highly functionalized fluorinated pyrazoles and pyrazolines has been developed. Flowing fluorinated amines through sequential reactor coils mediates diazoalkane formation and [3+2] cycloaddition to generate more than 30 azoles in a telescoped fashion. Pyrazole cores are then sequentially modified through additional reactor modules performing N-alkylation and arylation, deprotection, and amidation to install broad molecular diversity in short order. Continuous flow synthesis enables the safe handling of diazoalkanes at elevated temperatures, and the use of aryl alkyne dipolarphiles under catalyst-free conditions. This assembly-line synthesis provides a flexible approach for the synthesis of agrochemicals and pharmaceuticals, as demonstrated by a four-step, telescoped synthesis of measles therapeutic, AS-136A, in a total residence time of 31.7 min (1.76 g h?1).
Direct [3+2]-cycloaddition of electron-deficient alkynes with CF3CHN2: Regioselective one-pot synthesis of 3-trifluoromethylpyrazoles
Li, Feng,Wang, Jingjing,Pei, Wenlong,Li, Hong,Zhang, Huiling,Song, Manman,Guo, Linyun,Zhang, Anan,Liu, Lantao
supporting information, p. 4344 - 4347 (2017/10/17)
A direct and facile cycloaddition reaction of electron-deficient terminal alkynes with 2,2,2-trifluorodiazoethane under mild conditions to afford a series of 5-substituted 3-trifluoromethylpyrazoles in high yields is described. The potential application of this cycloaddition reaction was demonstrated via the efficient synthesis of a key intermediate of the antiviral drug AS-136A and a fluorinated analog of Tebufenpyrad.
Fluoroalkyl-Substituted Diazomethanes and Their Application in a General Synthesis of Pyrazoles and Pyrazolines
Mertens, Lucas,Hock, Katharina J.,Koenigs, Rene M.
supporting information, p. 9542 - 9545 (2016/07/14)
A novel continuous-flow approach for the synthesis of fluoroalkyl-substituted diazomethanes has been developed. Utilizing a cheap, self-made microreactor fluoroalkyl-substituted amines were transformed into the corresponding diazomethanes using tert-butyl nitrite and acetic acid as catalyst. These diazomethanes were employed in [2+3] cycloaddition reactions with olefins and alkynes, yielding valuable pyrazolines and pyrazoles in good to excellent yields.
Three-component synthesis of fluorinated pyrazoles from fluoroalkylamines, NaNO2 and electron-deficient alkynes
Mykhailiuk, Pavel K.
, p. 3438 - 3445 (2015/03/18)
Three-component reaction between RCF2CH2NH2·HCl, NaNO2 and electron-deficient alkynes significantly depends on substituent R . The reaction gives the fluorinated pyrazoles in high yields when R is a fluorine atom or a fluoroalkyl group. With other R unexpected products are formed.
Bidentate NHC pyrozolate ligands in luminescent platinum(ii) complexes
Naziruddin, Abbas Raja,Galstyan, Anzhela,Iordache, Adriana,Daniliuc, Constantin G.,Strassert, Cristian A.,De Cola, Luisa
supporting information, p. 8467 - 8477 (2015/05/20)
A bidentate C^N donor set derived from an N-heterocyclic carbene (NHC) precursor linked to a trifluoromethyl (CF3) functionalized pyrazole ring is described for the first time. The ligands have been employed to prepare four new phosphorescent complexes by the coordination of platinum(ii) centres bearing cyclometalated phenyl-pyridine/triazole-pyridine chelates. The electronic and steric environments of these complexes were tuned through the incorporation of suitable substituents in the phenyl-pyridine/triazole-pyridine ligands, wherein the position of the phenyl-ring substituent (a CF3 group) also directs the selective adoption of either a trans or a cis configuration between the CNHC and the Cphenyl donor atoms. Molecular structures obtained by X-ray diffraction for three of the complexes confirm a distorted square-planar configuration around the platinum centre, and DFT calculations show that the substituents have a significant influence on the energies of the frontier orbitals. Moreover, a platinum(ii) complex featuring the new bidentate NHC^pyrazolate ligand and a bulky adamantyl functionalized pyridine-triazole luminophore was observed to be highly emissive and exhibiting a sky-blue luminescence (λEm = 470 nm) with photoluminescence quantum yields as high as 50% in doped PMMA matrices. A complete photophysical investigation of all of the complexes in solution as well as in the solid state is herein reported.
1,3-dipolar cycloadditions of ethyl 2-diazo-3,3,3-trifluoropropanoate to alkynes and [1,5] sigmatropic rearrangements of the resulting 3H-pyrazoles: Synthesis of mono-, bis- and tris(trifluoromethyl)-substituted pyrazoles
Gladow, Daniel,Doniz-Kettenmann, Sebastian,Reissig, Hans-Ulrich
, p. 808 - 821 (2014/07/07)
The 1,3-dipolar cycloadditions of ethyl 2-diazo-3,3,3-trifluoropropanoate with electron-rich and electron-deficient alkynes, as well as the van Alphen-Hüttel rearrangements of the resulting 3H-pyrazoles were investigated. These reactions led to a series of CF3-substituted pyrazoles in good overall yields. Phenyl- and diphenylacetylene proved to be unreactive, but, at high temperature, the diazoalkane and phenylacetylene furnished a cyclopropene derivative. As expected, the 1,3-dipolar cycloaddition to the ynamine occurred much faster than those to electron-deficient alkynes. With one exception, all cycloadditions proceeded with excellent regioselectivities. The [1,5] sigmatropic rearrangement of the primary 3H-pyrazoles provided products with shifted acyl groups; products resulting from the migration of a CF3 group were not detected. In agreement with literature reports, this rearrangement occurs faster with 3H-pyrazoles bearing electron-withdrawing substituents. Copyright
One-pot synthesis of CF3-substituted pyrazolines/pyrazoles from electron-deficient alkenes/alkynes and CF3CHN2 generated in situ: Optimized synthesis of tris(trifluoromethyl)pyrazole
Slobodyanyuk, Evgeniy Y.,Artamonov, Olexiy S.,Shishkin, Oleg V.,Mykhailiuk, Pavel K.
, p. 2487 - 2495 (2014/05/06)
The [3+2] cycloaddition of CF3CHN2, generated in situ, with electron-deficient alkenes/alkynes affords CF3-substituted pyrazolines/pyrazoles in quantitative yields. The one-pot three-component reaction between CF3/su
