Synthesis of 2-aryl-4-phenyl-5-trifluoromethylimidazoles

Several 2-aryl-4-phenyl-5-trifluoromethylimidazoles have been made from the previously unknown 1-phenyl-3,3,3-trifluoro-1,2-propanedione monohdyrate. One analog, 4-phenyl-2,5-bis(trifluoromethyl)imidazole, is quite acidic, exhibiting pK_a 8.1.     

2-对氯苯氧基-5-芳基-1,3,4-噁二唑的合成

对氯苯氧乙酸乙酯与水合肼反应制得对甲基苯氧乙酰肼（2）;以碳酸钠作缚酸剂,2与卤代苯甲酰氯反应合成了N、N＇-二酰基肼（3）;在POCl3作用下,3脱水环化得2-对氯苯氧基-5-芳基-1,3,4-噁二唑,其结构经1^H NMR,IR,MS和元素分析表征,并对其裂解途径进行了探讨。     

Synthesis and reactions of 5-aryl-2-thiophenecarbaldehydes

The reaction of 2-thiophenecarbaldehyde with arene diazonium chlorides in the presence of CuCl₂ catalyst gave 5-aryl-2-thiophenecarbaldehydes. Use of 4-nitrobenzene diazonium chloride in the reaction also gave the isomeric 3-(4-nitrophenyl)-2-thiophenecarbaldehyde. Condensation products of the 5-aryl-2-thiophenecarbaldehydes with cyanoacetic acid esters, cyanoacetamide, and with barbituric and dimethylbarbituric acids were prepared. Communication 16 in the series “Synthesis of heterocycles based on the products of arylation of unsaturated compounds”. For Communication 15 see [1]. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1166–1171, August, 2008.     

2-苯基-5-芳基-1,3,4-噁二唑的合成与表征

苯甲酸乙酯与水合肼反应制得苯甲酰肼(1),1再分别与芳酰氯反应制得N、N′-二酰基肼(3a～3i),3a～3i在POCl3作用下脱水环化生成2-苯基-5-芳基-1,3,4-噁二唑(4a～4i)。其结构经元素分析,IR,^1H NMR和MS表征,并对其裂解途径进行了探讨。     

Synthesis of 1-aryl-5-chloropyrazoles

A method for obtaining 1-aryl-5-chloropyrazoles with vacant 3 and 4 positions by cyclization of 3,3-dichloro-2-propenal arylhydrazones is proposed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 42–45, January, 1990.     

2-对硝基苯基-5-芳基-1,3,4-噁二唑的合成与表征

以自制的N,N′-二酰基肼在POCl3作用下脱水环化,合成了8个2-对硝基苯基-5-芳基-1,3,4-噁二唑类化合物。其结构经^1H NMR,IR,MS和元素分析表征,并对其裂解途径进行了探讨。     

Synthesis and proton-acceptor capacities of 5-aryl-2-acetylthiophenes and 1-(5-aryl-2-thienyl)-1propenones

A number of 5-aryl-2-acetylthiophenes and 1-(5-aryl-2-thienyl)-3-phenyl-1-propenones were synthesized, and it was shown by means of their IR spectra that the 1-propenones are trans isomers with respect to the orientation of the substituents attached to the double bond and have an s-cis conformation. According to the data from the IR spectra of the H complexes of the investigated compounds with phenol, 5-aryl-2-acetylthiophenes have higher proton-acceptor capacities than acetophenones, 2-acetylthiophenes, and 4-acetyldiphenyl; a similar picture is also noted in a number of 1-propenones and 3-propenones. The transmission factors () obtained by Hammett correlation of the _Oh values for 1,4-phenylene, 2,5-thienylene, and vinylene groupings are identical and are equal to 0.8. It is shown on the basis of a correlation with respect to an equation of the Yukawa-Zuno type that the thiophene ring transmits polar conjugation better than the benzene ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1196–1202, September, 1976.     

Synthesis and spectral properties of 2-methyl-5-aryl-1,3,4-oxadiazoles

By heterocyclization of 1-acyl-2-aroylhydrazines under the influence of strong dehydrating substances, a series of 2-methyl-5-aryl-1,3,4-oxadiazoles has been synthesized and their UV, IR, and PMR spectra have been investigated. Through analysis of data on the influence of substituents on the position of the maximum in the electronic absorption spectrum, together with calculated data, it has been shown that the long-wave band of 2-methyl-5-phenyl-1,3,4-oxadiazole is due to an S₀–S₁ transition of the –^* type and that it is a charge transfer band for transfer from the phenyl radical to the oxadiazole ring; the 1,3,4-oxadiazole ring as a substituent has an electron-acceptor character.Institute of Single Crystals, National Academy of Sciences of the Ukraine, Khar'kov 310001. Khar'kov State University, Khar'kov 310077. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 816–821, June, 1997.     

Synthesis of 5-aryl-2-alkoxyfuranes from 1-aroyl-2,2-dichlorocyclopropanes

The reaction of 1-aroyl-2,2-dichlorocyclopropanes with a mixture of potassium tertbutylate and potassium methylate (or ethylate) in tert-butyl alcohol gives 5-aryl-2-methoxy (or ethoxy) furanes in good yield.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1603–1605, December, 1984.     

2-(2-三氟苯基)-5-芳基-1,3,4-噁二唑类化合物的合成

2-三氟苯甲酰肼与芳酰氯反应制得N,N′-二酰肼(2)。2在三氯氧磷存在下脱水闭环,合成了一系列2-(2-三氟苯基)-5-芳基-1,3,4-噁二唑类化合物,其结构经1H NMR,IR,MS和元素分析表征。     

Photochemical behaviour of 5-bromo-2-furyl ketones : Synthesis of 5-aryl-2-furyl ketones

The photochemical behaviour of the compound 8 was studied. The irradiation of a 10^-3M solution of 8 in aromatic solvents gave high yields of 9 The irradiation of 8 in ethereal or amine solution quantitatively gave 10 The comparison of reaction rates and quantum yields in different solvents gave results in agreement with the hypothesis of an exciplex formation.     

Synthesis and structure of 5-hydrazino- and 5-hydroxyamino-3-aryl-2-pyrazolines and-2-isoxazolines

It was established by the methods of ¹H and ¹³C NMR spectroscopy that the oximohydrazones and bis(hydrazones) of aroylacetic aldehydes exist in the form of the corresponding 5-hydrazino- and 5-hydroxyamino-3-aryl-2-pyrazolines and -2-isoxazolines. The features of the aromatization of these compounds to the corresponding pyrazoles and isoxazoles were studied. Data on the mass-spectral study of the 5-hydroxyamino-2-pyrazoline-5-hydrazino-2-isoxazoline tautomerism in the gas phase are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 927–935, July, 1989.     

Synthesis of 5-aryl-2-oxazolepropionic acids and analogs. Antiinflammatory agents

Condensation of 2-bromoacetophenones with sodium succinimide gave N-phenacylsuccinimides ( 1 ) which were opened with sodium hydroxide to N-phenacylsuccinamic acids ( 2 ). The latter were cyclized to 5-aryl-2-oxazolepropionic acids ( 3 ) in sulfuric acid. Similar cyclization of N-phenacylphthalamic acid ( 5 ) and succinic acid 2-benzoylhydrazide ( 7 ) gave o-(5-phenyl-2-oxazolyl)benzoic acid ( 6 ) and 5-phenyl-1,3,4-oxadiazole-2-propionic acid ( 8 ). The succinamic acids 2 and the phthalamic acid 5 were observed to recyclize to the corresponding imides ( 1 and 4 ) on heating, and the succinic acid hydrazide 7 was similarly cyclized to N-benzamidosuccinimide ( 9 ) with acetic anhydride. Antiinflammatory screening data are reported for 3 , 6 and 8 .     

Synthesis of New Type Azo Compounds 2-Aroylazo-5-aryl-1,3,4-oxadiazole

Azo Compounds are important for their uses as dyes and analytical reagents. Optical-switch and image storage can be made by azobenzenes liquid crystal Recently, scientists are especially interested in new type azo compounds fir they can be used as photoconductive and photochromism materials. However these kinds of azo compounds were limited because of the limited synthesis methods.     

3-N-乙酰基-2-芳基-5-苯基-1,3,4-噁唑啉类化合物的合成与表征

以自制的苯甲酰腙与乙酸酐环合,高收率地合成了3-N-乙酰基-2-芳基-5-苯基-1,3,4-噁唑啉类化合物。其结构经^1H NMR,IR,MS和元素分析表征,并对其质谱碎片裂解途径进行了探讨。     

Synthesis of 2-amino-4-aryl-3-cyano-5-hydroxyimino-4,5-dihydrothiophenes

The Michael addition of cyanothioacetamide to nitrostyrenes was investigated. Previously unknown 2-amino-4-aryl-3-cyano-5-hydroxyimino-4,5-dihydrothiophenes were obtained. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1472–1477, October, 2007.     

Synthesis of 1-aryl-2-propanones

A new convenient synthesis of a series of 1-aryl-2-propanones using aromatic amines as precursors, via diazo-reaction and improved Meerwein arylation reaction under mild conditions, was achieved. In addition, 1-[3,5-bis(trifluoromethyl)phenyl]-2-propanone is a new compound among the synthesized compounds. This approach is an efficient synthetic method for the aryl-propanones with different substituting groups. __________ Translated from Chinese Journal of Organic Chemistry, 2007, 27(10): 1244–1249 [译自: 有机化学]     

Synthesis and stereochemistry of 2, 2-dimethyl-5-aryl-4-benzoyl-1,3-dioxolanes

The reaction of 3-aryl-2-benzoyloxiranes with acetone in the presence of catalytic amounts of boron trifluoride etherate leads to the formation of mixtures of cis and trans isomers (3070) of 2,2-dimethyl-5-aryl-4-benzoyl-1,3-dioxolanes, the structures and stereochemistry of which were established on the basis of data from their PMR spectra, measurement of the Overhauser nuclear effect, and some chemical transformations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 888–891, July, 1979.