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1.
Mironov V. F. Borisova Yu. Yu. Burnaeva L. M. Gubaidullin A. T. Dobrynin A. B. Litvinov I. A. Musin R. Z. Konovalova I. V. 《Russian Chemical Bulletin》2010,59(4):820-827
Phosphorylation of 2-hydroxyphenyl 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl ketone with dichloro(phenyl)phosphine
gave 5-oxo-2-phenyl-4,4-bis(trifluoromethyl)-4,5-di-hydro-1,3,2-benzodioxaphosphepine. Heating of the latter initiated an
intramolecular interaction of the P atom with the carbonyl group. Hydrolysis of the intermediate product yielded 3-hydroxy-2-oxo-2-phenyl-3-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]-2,3-di-hydro-1,2λ5-benzo[d]oxaphosphole. The reaction was highly stereoselective (PRCS/PSCR). The reaction of the starting phosphepine with chloral proceeded highly stereoselectively (PRCSCS/PSCRCR) to give a 5-carbaphosphatrane derivative containing a four-membered ring, namely, 1-phenyl-3-trichloromethyl-10,10-bis(trifluoromethyl)-6,7-benzo-2,4,8,9-tetraoxa-1λ5-phosphatricyclo[3.3.2.01,5]decene. The trigonal bipyramid of the 5-carbaphosphatrane derivative is made up of the equatorial O atoms and the apical
C atoms. 相似文献
2.
Mara E. F. Braibante Gunter Clar Marcos A. P. Martins 《Journal of heterocyclic chemistry》1993,30(4):1159-1160
1-Methyl-5-(trifluoromethyl)-1H-pyrazoles 2, 3 and 4,5-dihydro-1-phenyl-5-(trifluoromethyl)-1H-pyrazol-5-ol 4 were prepared by reaction of 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones 1 and hydrazine, methylhydrazine, and phenylhydrazine, respectively, in good yields. Compound 1 proved to be a versatile building block for the regiospecific construction of pyrazole rings having an 5-trifluoromethyl substituent. 相似文献
3.
《Mendeleev Communications》2023,33(2):194-196
Methyl 4-trifluoro-2-isopropyl-4-oxobutanoate prepared by the improved procedure was cyclized with hydrazines to afford the title pyrazole derivatives. N- and O-alkylation of 4-isopropyl-1-phenyl-3-(trifluoromethyl)pyrazol-5-ol gave trifluoromethyl analogues of Propyphenazone and 5-alkoxy derivatives. 4-Isopropylpyrazoles containing O-butoxy moiety with a terminal trifluoromethyl or acyloxy group were found to demonstrate a promising analgesic activity. 相似文献
4.
Ethyl 1-aryl-5-(trifluoromethyl)-1H-pyrazole-4-carboxylates 2 were prepared by the condensation of arylhydrazines with ethyl 3-ethoxy-2-(trifluoroacetyl)-2-propenoate (1a) at low temperature. The corresponding acids were also synthesized. X-ray diffraction analysis of an amide derivative 4 verified the position of the trifluoromethyl group on the pyrazole ring. 相似文献
5.
The reaction of methyl 2-bromo-6-(trifluoromethyl)-3-pyridinecarboxylate ( 1 ) with methanesulfonamide gave methyl 2-[(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridine-carboxylate ( 2 ). Alkylation of compound 2 with methyl iodide followed by cyclization of the resulting methyl 2-[methyl(methylsulfonyl)amino]-6-(trifluoromethyl)-3-pyridinecarboxylate ( 3 ) yielded 1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 4 ). The reaction of compound 4 with α,2,4-trichlorotoluene, methyl bromopropionate, methyl iodide, 3-trifluoromethylphenyl isocyanate, phenyl isocyanate and 2,4-dichloro-5-(2-propynyloxy)phenyl isothiocyanate gave, respectively, 4-[(2,4-dichlorophenyl)methoxy]-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazine 2,2-dioxide ( 5 ), methyl 2-[[1-methyl-2,2-dioxido-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4-yl]oxy]propanoate ( 6 ), 1,3,3-trimethyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2]thiazin-4(3H)-one 2,2-dioxide ( 7 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-[3-(trifluoromethyl)phenyl]-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 8 ), 4-hydroxy-1-methyl-7-(trifluoromethyl)-N-phenyl-1H-pyrido[2,3-c][1,2]thiazine-3-carboxamide 2,2-dioxide ( 9 ) and N-[2,4-dichloro-5-(2-propynyloxy)phenyl]-4-hydroxy-1-methyl-7-(trifluoromethyl)-1H-pyrido[2,3-c][1,2] thiazine-3-carboxamide 2,2-dioxide ( 10 ). 相似文献
6.
L. V. Saloutina A. Ya. Zapevalov M. I. Kodess V. I. Saloutin G. G. Aleksandrov O. N. Chupakhin 《Russian Journal of Electrochemistry》2000,36(6):887-898
Reactions of polyfluoro-2,3-epoxyalkanes with thiourea and thiosemicarbazide afforded 2-amino-4-hydroxy-4,5-di(polyfluoroalkyl)-5-fluoro-l,3-thiazolines
and 2-hydrazino-4-hydroxy-4,5-di(polyfluoroalkyl)-5-fluoro-l,3-thiazolines respectively. Unsymmetrical oxiranes furnish mixtures
of regioisomeric heterocyclic compounds, and the epoxy cycle is predominantly cleaved from the side of bulkier fluoroalkyl
group. The reactions of E-oxiranes are stereospecific and provide 1,3-thiazolines in the E-form. The structure of compounds
obtained was confirmed by IR,19F,1H, and13C NMR spectroscopy, by mass spectra and chemical transformations. E-isomers of 2-amino-4-hydroxy-4,5-bis(trifluoromethyl)-5-fluoro-l,3-thiazoline
and 2-amino-5-heptafluoropropyl-4-hydroxy-4-trifluoromethyl-5-fluoro-1,3-thiazoline were subjected to X-ray diffraction analysis.
The study was carried out under financial support of the Russian Foundation for Basic Research (grant no. 00-03-332767), and
the Foundation for Support of the Leading Scientific Schools (grant no. 00-15-97390). 相似文献
7.
Helio G Bonacorso Hilario Lewandowski Roberta L Drekener Michelle B Costa Claudio M.P Pereira Arci D Wastowski Clóvis Peppe Marcos A.P Martins Nilo Zanatta 《Journal of fluorine chemistry》2003,122(2):159-163
A new series of six 3-aryl-5-hydroxy-5-trifluoromethyl-4,5-dihydro-1H-1-picolinoylpyrazole hydrochlorides were synthesised in one-step in high yields by the reaction of β-methoxyvinyl trifluoromethyl ketones with 2-pyridinecarboxamidrazone in the presence of hydrochloric acid. The hydrochloride salts were easily converted to the respective new series of free trifluoromethylated 4,5-dihydro-1H-1-picolinoylpyrazoles using triethylamine in anhydrous diethyl ether. X-ray structure and NMR data from the pyrazole hydrochlorides are reported. 相似文献
8.
James W. Pavlik Theppawut Israsena Na Ayudhya Supawan Tantayanon 《Journal of heterocyclic chemistry》2002,39(5):1025-1027
In contrast to previous reports, 4‐ethoxy‐1,1,1‐trifluoro‐3‐buten‐2‐one ( 1 ) was observed to react with methylhydrazine ( 2 ) in refluxing ethanol to yield 1‐methyl‐3‐(trifluoromethyl)pyrazole ( 6 ) and 4,5‐dihydro‐1‐methyl‐5‐(trifluoromethyl)pyrazol‐5‐ol ( 4 ). The later compound undergoes acid catalyzed dehydration to 1‐methyl‐5‐(trifluoromethyl)pyrazole ( 3 ). 相似文献
9.
Yuhki Ohtsuka Daisuke Uraguchi Kyoko Yamamoto Kenji Tokuhisa Tetsu Yamakawa 《Tetrahedron》2012,68(12):2636-2649
Direct trifluoromethylation of 1,3-dicarbonyl compounds with CF3I in the presence of a Fenton reagent in dimethylsulfoxide was investigated. 1,3-Diketones, 3-oxocarboxylates and 3-oxocarboxamides were readily trifluoromethylated at the methylene carbon between two oxo groups. Cycloaddition of hydrazine derivatives to the obtained 2-(trifluoromethyl)-1,3-dicarbonyl compounds provided fluorinated pyrazoles. 4-(Trifluoromethyl)pyrazole derivatives were formed from 2-(trifluoromethyl)-1,3-diketones, while 3-oxo-2-(trifluoromethyl)carboxylates or carboxamides gave 5-fluoropyrazole-4-carboxylates or carboxamides, respectively, via 3-hydrazono-2-(trifluoromethyl)carboxylates or carboxamides as an intermediate. 相似文献
10.
Trifluoromethylated molecules, as well as pyrazol-3-one derivatives, are found in a wide range of biologically active compounds. An highly facile, green and mild access to substituted 3-(trifluoromethyl)-4,5-dihydro-1H-furo[2,3-c]pyrazole derivatives by the cascade [3 + 2] Michael/Alkylation of unsaturated pyrazolones with α-bromomalonate has been developed. The reactions can be performed in a easily available and environmentally benign solvent, and the substituted 3-(trifluoromethyl)-4,5-dihydro-1H-furo[2,3-c]pyrazole derivatives can be obtained in good to excellent yields by a simple purification step. The antifungal activities of these functional pyrazole derivatives were also evaluated and they showed high antifungal activity against Alternaria solani. 相似文献
11.
Yu. Yu. Kotorova A. T. Gubaidullin V. F. Mironov L. M. Burnaeva A. B. Dobrynin R. Z. Musin I. A. Litvinov I. V. Konovalova 《Russian Journal of General Chemistry》2006,76(3):437-446
The reaction of hexafluoroacetone with 2-alkoxy-6(7)-chloro-1,3,2-benzodioxaphosphorin-4-ones yielded 7-and 8-chloro-substituted 2-alkoxy-2,5-dioxo-4,4-bis(trifluoromethyl)-1,3,2λ5-benzodioxaphosphepines. Their steric structure was studied by single-crystal X-ray diffraction. The effect of fluorinated substituents on the crystal packing of the benzophosphepines was demonstrated. Hydrolysis of these compounds gave the corresponding 4-and 5-chloro-substituted 2-(2-hydroxyphenyl)-2-oxo-1,1-bis(trifluoromethyl)-ethanols; the structure of 2-(2-hydroxy-5-chlorophenyl)-2-oxo-1,1-bis(trifluoromethyl)ethanol was also proved by single-crystal X-ray diffraction. 相似文献
12.
A. V. Zerov T. S. Krupenya A. A. Petrov S. I. Yakimovich 《Russian Journal of Organic Chemistry》2015,51(12):1758-1761
Reactions of 1,1,1-trifluoropentane-2,4-dione and 1,1,1,5,5,5-hexafluoropentane-2,4-dione with 2-aminobenzohydrazide afforded (2-aminophenyl)[5-hydroxy-3-methyl-5-(trifluoromethyl)- and (2-aminophenyl)[ 5-hydroxy-3,5-bis(trifluoromethyl)-4,5-dihydropyrazol-1-yl]methanones, respectively. 4-Ethoxy-1,1,1- trifluorobut-3-en-2-one reacted with 2-aminobenzhydrazide to give 2-(trifluoromethyl)-3a,4-dihydropyrazolo-[5,1-{ptb}]quinazolin-9(3{ptH})-one. 相似文献
13.
The pK
a values of N-heterocyclic compounds (substituted pyrazoles) in a 70% (v/v) dioxane-water mixture have been determined using
pH-metric measurements. The stability constants of the complexes of Dy(III), Nd(III), Sm(III), and Tb(III) with 3-(2-hydroxyphenyl)-5-methylpyrazole,
l-phenyl-3-(2-hydimyphenyl)-5-methylpyrazole 3-(2-hydroxy-4-methylphenyl)-5-methylpyrazole, and l-phenyl-3-(2-hydroxy-4-methylphenyl)-5-methylpyrazole
have been determined by the pH-metric method at ( 300 ± 0.1) K. The effect of ionic strengths on the complexes of Sm3+ and Pr3+ ions with pyrazole has been investigated in the internal from 0.02 to 0.1 mol dm−3 (sodium perchlorate) in the pH range 2–3. 相似文献
14.
John P. Chupp 《Journal of heterocyclic chemistry》1994,31(6):1377-1380
Utilizing the recently reported compound, 1-methyl-5-(trifluoromethyl)-2,3,4,5-tetrahydropyrazol-3-one, 4 , a series of regional isomers of 1-methyl-5-(trifluoromethyl)-3-chloropyrazole, newly substituted in the 4-position were prepared by original syntheses. Chief among them was the new regional 4-hydroxy isomer, 3a , a linkage reagent valuable for preparing new SAR candidates in the bio-active pyrazole phenyl ether series. 相似文献
15.
Ralph-Matthias Schoth Dmitrii Sevenard Kazimir Pashkevich Gerd-Volker Rschenthaler 《Coordination chemistry reviews》2000,210(1):101-134
The role of fluorinated β-diketones, their tautomers (keto–enols) and their derivatives as reagents towards λ3P compounds is reviewed, including 2-trifluoroacetyl phenols, possessing formally a keto–enol system, and their derivatives. In an ‘insertion’ reaction phosphine and the keto–enol tautomers of 1,1,1,5,5,5-hexafluoro- and 1,1,1-trifluoropentan-2,4-dione furnished primary (S) or (R) α-hydroxy phosphines, whose enol functions probably isomerized the corresponding keto compounds. Further addition and isomerisation furnished 1,3α,5,7β-tetrakis(trifluoromethyl)-2-phospha-6-oxa-9-oxabicyclo[3.3.1]-nonan-3β,7α-diol and 1,7-trifluoromethyl-3,5-methyl-2,4,8-trioxa-6-phophaadamantane, exclusively one diastereomer in each case. The main mechanistic feature of these reactions is a consecutive diastereoselective hemiketal cyclization. 1,1,1,5,5,5-Hexafluoro- and 1,1,1-trifluoropentan-2,4-dione, as well as 2-trifluoroacetyl phenol and its imino derivatives reacted diastereospecifically with phosphonous acid dichlorides, RPCl2 to give in a concerted mechanism thermally stable tricyclic λ5σ5P phosphoranes containing two five-membered rings and one six-membered ring. Surprisingly, the two CF3 groups bonded to an sp3-hybridized carbon were in a cisoid arrangement having closest non-bonding FF distances of 301.4 or 273.5 pm. These findings reflect the ‘through space’ F---F coupling constants of the tricyclic phosphoranes (JFF=4.0–7.0 Hz), in solution. 4,4,4-Trifluoro-3-hydroxy-1-phenyl-butan-1-one and methyl or phenyl phosphonous acid dichlorides gave similar tricyclic phosphoranes decomposing at ambient temperature to furnish 1,2λ5σ4-oxaphospholanes and (E)-1,1,1-trifluoro-4-phenyl-but-2-en-4-one. Dialkylphosphites and 1,1,1,5,5,5-hexafluoropentan-2,4-dione reacted to give either the (Z)-enol phosphonates or the respective γ-ketophosphonates from which in two cases four diastereomeric 2-oxo-2,5-dialkoxy-3,5-bis(trifluoromethyl)-3-hydroxy-1,2λ5σ4-oxa-phospholanes were obtained. 2-Trifluoroacetyl cyclohexanone, 4,4,4-trifluoro-3-trimethylsiloxy-1-phenylbutan-1-one, 1-benzoyl-2-trifluormethyloxirane, 1-benzoyl-2-trifluoro-methylaziridine, 2-trifluoroacetyl-1-trimethylsiloxybenzene and (trifluoroacetyl-1-phenyl) diethyl phosphate reacted with tris(trimethylsilyl) phosphite to give functionalized α-trimethylsiloxy phosphonates, which could easily be transferred into the respective phosphonic acids. In the case of an oxirane and an aziridine ketone no ring cleavage was observed. For 1,1′-(2-hydroxy-5-methyl-m-phenylene)-bis-ethanone and 1,1′-(2-trimethylsiloxy-5-methyl-m-phenylene)-bis-ethanone benzoxaphospholanes were obtained. Trialkyl phosphites and 1,1,1,5,5,5-hexafluoropentan-2,4-dione furnished cyclic phosphoranes containing the 3-hydroxy-3,5-bis(trifluoromethyl)-1,2λ5σ5-oxaphospholene structural element, stable at ambient temperature only in the case of one cyclic phosphite precursor. (E)-1,1,1-Trifluoro-4-phenyl-but-2-en-4-one and trimethylphosphite reacted to form 1,2λ5σ5-oxaphosphol-4-ene as the sole product. Results similar to the reaction of 1,1′-(2-hydroxy-5-methyl-m-phenylene)-bis-ethanone with diethyltrimethylsilylphosphite were obtained for trimethylphosphite and 2-trifluoroacetyl phenol where a deoxygenated phosphorane was found, easily hydrolyzed to give the respective phosphonic acid. With dialkylisocyanato phosphites and the keto components, 1,1,1,5,5,5-hexafluoro- and 1,1,1-trifluoropentan-2,4-dione, 4,4,4-trifluoro-1-phenyl-1,3-butandione, 2-trifluoroacetyl cyclohexanone, 2-trifluoroacetyl phenol and 1,1′-(2-hydroxy-5-methyl-m-phenylene)-bis-ethanone reacted in a ‘double’ cycloaddition to form bicyclic phosphoranes containing the 4,8-dioxa-2-aza-1λ5σ5-phosphabicyclo[3.3.0]-oct-6-en-3-one ring system; for the imino derivatives of 2-trifluoroacetyl phenol a corresponding 8-oxa-2,4-diaza- system was generated. For (E)-1,1,1,5,5,5-hexafluoro-4-trimethylsiloxy-3-penten-2-one however, a cyclic spiroimino phosphorane was obtained which underwent a [2+2] cyclodimerization to form a diazadiphosphetidine. Dimethylpropynyl phosphonite and 1,1,1,5,5,5-hexafluoropentan-2,4-dione yielded diastereoselectively a bisphosphorane, namely 1,4-bis(trifluoromethyl)-3,6-dioxa-2,2,7,7-tetramethoxy-2,7-di(1-propynyl)-2,7-diphosphabicyclo[2.2.1] heptane. When trimethylsilanyl–phosphenimidous acid bis-trimethylsilanyl–amide, Me3SiN=PN(SiMe3)2, was allowed to react with 1,1,1,5,5,5-hexafluoro- and 1,1,1-trifluoropentan-2,4-dione, (E)-1,1,1,5,5,5-hexafluoro-4-trimethylsiloxy-3-penten-2-one, 2-trifluoroacetyl cyclopentanone, 2-trifluoroacetyl phenol and its imino derivatives, 2-imino-1,2λ5σ4-oxaphospholenes were found containing two diastereomers in each case, which added hexafluoroacetone across the P=N bond to give 1,3,2λ5σ5-oxazaphosphetanes. 相似文献
16.
Olugbeminiyi O. Fadeyi 《Tetrahedron letters》2008,49(32):4725-4727
A simple synthesis of 5-(trifluoromethyl)cyclohexane-1,3-dione and 3-amino-5-(trifluoromethyl)cyclohex-2-en-1-one from the sodium salt of methyl or ethyl-4-hydroxy-2-oxo-6-(trifluoromethyl)cyclohex-3-en-1-oate is demonstrated. The compounds represent highly functionalized reactive intermediates for the synthesis of organic and heterocyclic compounds containing a trifluoromethyl group. 相似文献
17.
Reactions of 3-(polyfluoroacyl)chromones with acetoacetamide and ethyl acetoacetate in the presence of ammonium acetate proceed at the C-2 atom of the chromone system with pyrone ring-opening and subsequent cyclization to 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinamides, ethyl 5-salicyloyl-2-methyl-6-(trifluoromethyl)nicotinates, and ethyl 5-hydroxy-2-methyl-5-(polyfluoroalkyl)-5H-chromeno[4,3-b]pyridine-3-carboxylates. Similar reaction with β-aminocrotononitrile gave 5-hydroxy-2-methyl-5-(polyfluoroalkyl)-5H-chromeno[4,3-b]pyridine-3-carbonitriles. 相似文献
18.
Synthesis of a tritium-labeled, fipronil-based, highly potent, photoaffinity probe for the GABA receptor 总被引:1,自引:0,他引:1
3-[4-[1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazolo]]-3-(trifluoromethyl)diazirine is a fipronil-based (i.e. fiprole), high-affinity probe for the GABA receptor. For synthesis of the tritium-labeled version of this trifluoromethyldiazirinylfiprole ([(3)H]TDF) the required intermediate, 3-[4-[1-(2,6-dichloro-3-iodo-4-trifluoromethylphenyl)-5-iodopyrazolo]]-3-(trifluoromethyl)diazirine, was prepared in 10 steps from pyrazole and 3,5-dichloro-4-fluorobenzotrifluoride. One of the key transformations was lithiation and subsequent iodination of the 4-(2,2,2-trifluoro-1-hydroxyethyl)pyrazole intermediate. The last step involved reduction of the diiodofiprole with tritium, Pd/C, and triethylamine in ethyl acetate and afforded [(3)H]TDF with a specific activity of 15 Ci/mmol and 99% radiopurity. 相似文献
19.
Sophia Mitkidou Stelios Papadopoulos Julia Stephanidou-Stephanatou 《Journal of heterocyclic chemistry》1991,28(6):1497-1499
The 1H and 13C nmr chemical shifts are used for the structural assignment of isomeric 1-aroyl-4,5-dihydro-5-hydroxy-4,4-dimethyl-1H-pyrazoles 1 unsymmetrically substituted with phenyl or methyl in the 3,5-positions of the pyrazole ring. The 1H nmr spectra of 1-aroyl- or 1-acetyl-4-methyl-1H-pyrazoles 2 are useful in structure elucidation of unsymmetrically 3- or 5-methyl substituted derivatives. 相似文献
20.
As part of a program to develop novel mechanism based skeletal muscle relaxants we identified 5-amino-3-hydroxy-1H-pyrazole-1-carboxamide (1) as a potential structural lead. This highly functionalized pyrazole was prepared via a published procedure [1] (Scheme 1, R1 = R1 = H), which utilized 3,5-dimethyl-1H-pyrazole-1-carboxamide as an aminocarbonyl transfer reagent, to give with cyanoacethydrazide the semicarbazide intermediate 6 . Base catalyzed cyclization of 6 afforded the initial lead compound. This reaction scheme was extended to the synthesis of additional 4-alkyl- and 4-aryl-5-amino-3-hydroxy-1H-pyrazole-1-carboxamides (Table 1). 相似文献