Stereoselective synthesis of cis-4,7-disubstituted 4,7-dihydroxy-4,7-dihydro[2.2]paracyclophanes

The nucleophilic addition of butyllithium, phenyllithium, methyllithium, and triallylborane to [2.2]paracyclophane-4,7-quinone (1) proceeded regio- and stereospecifically to give the corresponding cis-4,7-disubstituted 4,7-dihydroxy-4,7-dihydro[2.2]paracyclophanes 2—5 with the endo orientation of the hydroxy groups. The structures of quinone 1 and diols 2, 4, and 5 were established by X-ray diffraction analysis.     

5-芳胺-4,7-吲唑二酮的合成

以1,4-对醌、芳肼为原料,通过Aza-Nenitzescu反应、氧化银氧化得到吲唑醌,亲核试剂(各种芳香胺)在Ce3 催化下与吲唑醌发生迈克尔加成反应,得到一系列5-芳氨基基取代的吲唑醌.化合物结构经元素分析、IR及1H NMR证实.初步的生理活性研究表明,这些化合物具有良好的抗哮喘活性.     

4,7-二甲氧基-N-乙酰神经氨酸的合成

对4,7-二甲氧基-N-乙酰神经氨酸合成方法进行了研究和改进.以N-乙酰神经氨酸为起始原料,经酯化、缩醛保护、甲基化及水解开环等7个反应,通过四步操作制得目标产物.该路线避免了毒性试剂硫酸二甲酯和危险试剂氢化钠的使用,而且操作简单,条件温和,重复性好.     

Oxidation of 4,7-phenanthroline derivatives

Oxidation of 1,3-diphenyl-4,7-phenanthroline with potassium permanganate in alkaline medium results in transformation of the 4,7-phenanthroline ring system into 1,8-diaazafluorenone. Oxidation of 12-aryl-and 12-aryl-9,9-dimethyl-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones (condensation products of 6-arylmethylene-aminoquinolines with 1,3-cyclohexanedione and dimedone) with sodium nitrite in acetic acid leads to 12-aryl-9,10-dihydro-8H-benzo[b][4,7]phenanthrolin-11-ones. 13-Aryl-7,13-dihydro-12H-indeno-[2,1-b][4,7]phenanthrolin-12-ones obtained by reaction of 6-arylmethyleneaminoquinolines with 1,3-indandione are oxidized to 13-aryl-12H-indeno[2,1-b][4,7]phenanthrolin-12-ones on heating in nitrobenzene.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 9, 2004, pp. 1369–1375.Original Russian Text Copyright © 2004 by Gusak, Kozlov, Tereshko.     

Synthesis of quinolyl-substituted 4,7-phenanthrolines

1-(2-Quinolyl)-3-aryl-4,7-phenanthrolines were synthesized by reacting arylidene-6-quinolylamines with 2-acetylqidnoline in n-butanol in the presence of hydrochloric acid. It was found that the formation of the 4,7-phenanthroline ring is preceded by the stage of formation of an intermediate aminoketone, 1-(2-quinolyl)-3-phenyl-3-(6-quinolylamino)propan-1-one. The IR, UV, PMR, and mass spectra of the synthesized compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 796–800, June, 1990.     

Synthesis of 1,3-diaryl-4,7-phenanthrolines

A number of new 1,3-diaryl-4,7-phenanthrolines were synthesized by heterocyclization of arylidene-6-quinolylamines with acetophenones in the presence of an acidic catalyst. Intermediate amino ketones and side products, viz., N-(R¹-benzyl)-6-quinolylamines and ,-unsaturated ketones, were isolated. The IR, UV, PMR, and mass spectra of the synthesized compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1398–1401, October, 1985.     

4,7-二苯基-1,10-菲啰啉的合成研究

以4-苯基-8-硝基喹啉为起始原料,经还原得到4-苯基-8-氨基喹啉,再以I2/KI为氧化剂,在乙酸和盐酸的存在下,用Skraup法合成了4,7-二苯基-1,10-菲啰啉.化合物结构经IR和1H NMR得到了证实.实验研究得到了最佳的合成条件为:n(3-氯苯丙酮)∶n(4-苯基-8-氨基喹啉)=1.5∶1,I2/KI用量为8%,反应温度120℃,反应时间2.5 h.产品收率可达82%.     

Synthesis of 4,7-phenanthroline methyl derivatives

6-Aminoquinaldine condensation with aromatic aldehydes and cyclic -diketones (1,3-cyclohexanedione or dimedone) in butanol afforded new 12-aryl-3-methyl-8,9,10,12-tetrahydro-7H-benzo[b][4,7]phenanthrolin-11-ones and their 9,9-dimethyl derivatives.Translated from Zhurnal Organicheskoi Khimii, Vol. 40, No. 11, 2004, pp. 1709–1714.Original Russian Text Copyright © 2004 by Gusak, Tereshko, Kozlov.     

Spectral-luminescence and acid-base properties of 4,7-diaminocoumarins

The absorption and luminescence spectra of a series of 4,7-diaminocoumarins have been investigated in ethanol and acetonitrile solution. The pk_a ^I and pk_a ^II values for several of the compounds have been measured. It has been found that the site of primary protonation is the nitrogen atom in the 7-position, and that the second protonation reaction occurs at the lactone oxygen atom. The effects of steric and electronic factors on the spectral-luminescence and acid-base characteristics of these compounds are discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1610–1618, December, 1990.     

A facile access to masked isobenzofurans ; High exo-stereoselectivity in the Diels-Alder reactions of 4,7-dihydro-4,7-ethanoisobenzofuran.

The isobenzofuran derivatives precursors 4a-c are readily prepared from 1 ; their Diels-Alder adducts with cis-dienophiles present a stereochemistry endoexo from 4b,c and, interestingly, only exo (towards the furan moiety) from 4a.     

4,7-非对称二取代苯并噻二唑的合成

以邻甲苯胺为起始原料,经3步反应制得4-甲基-2,1,3-苯并噻二唑(1);1经溴代、水解和IBX选择性氧化制得系列4,7-非对称二取代苯并噻二唑砌块;通过砌块4-甲酰基-7-溴-2,1,3-苯并噻二唑与给电子基团的缩合或偶联反应,合成了具有4,7-非对称苯并噻二唑D-π-A型分子结构的新化合物4-甲酰基-7-N,N-二甲氨基-2,1,3-苯并噻二唑和4-甲酰基-7-[4-(N,N-二甲氨基)]苯基-2,1,3-苯并噻二唑,其结构经NMR和HR-MS表征.     

Spectral-luminescence characteristics of 1,3-diaryl-4,7-phenanthrolines

The effect of the nature of the substituents and the solvent on the absorption and fluorescence spectra and the fluorescence quantum yields of 1,3-diaryl-4,7-phenanthrolines was studied. Electron-donor groups in the para position of the phenyl ring cause a bathochromic shift of the absorption and fluorescence spectra and an increase in the fluorescence quantum yields. A change in the polarity of the solvent leads to a significant shift of the fluorescence spectra of hydroxy and dialkylamino derivatives of 4,7-phenanthroline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1651–1654, December, 1987.     

Benzimidazolediones. 1,4-addition reactions of 4,7-benzimidazoledione

A number of 1,4-addition reactions of 4,7-benzimidazoledione with hydrogen halides, thiols and amines are described.     

Jodzahlbestimmung von Fetten mit Hilfe von 4,7-Dichlorchinolin-bromid-perbromid

Ohne Zusammenfassung

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Determination of the iodine number of fats by means of 4,7-dichloroquinoline hydrobromide perbromide