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1.
Nonphotochromic fulgides of the indole series, which undergo E, Z isomerization under UV irradiation, were obtained from 1,2-dimethyl-3-formylindole and esters of aryl- and alkylmethylene-substituted itaconic acids by Stobbe condensation in the presence of strong bases.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 201–205, February, 1989.  相似文献   

2.
The reactions of 1-methyl-2-formylindole with the diethyl esters of alkyl- and phenylmethylene-substituted itaconic acids led to the production of photochromic fulgides, which formed deeply colored 5,8b-dihydrocarbazole derivatives during UV irradiation. It was found by PMR that the fulgides also undergo E,Z isomerization during UV irradiation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 907–910, July, 1989.  相似文献   

3.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 422–423, March, 1992.  相似文献   

4.
Molecular design, synthesis and photochromic properties of spirooxazines and fulgides are described. In the case of fulgides, the change of the substituents may lead to different photochromic properties and different photoreactions of the kind of compounds. In photochromic process of pyrryl-substituted fulgides, the excited singlet state is the mam species, but the excited triplet state is also involved. However, no excited triplet state has been observed in cyclization of aryl-substituted fulgides. In the case of spirooxazines, the substituents at 2'-position have great effect on the formation of photoproduct and on the mechanism of photoreaction. The increase of steric hindrance of the 2'-position substituent gives rise to the decrease of the quantum yield for the formation of photochromic merocyanine (PMC) and the increase of the relative quantum yield for the charge separated twist intermediate (CT).  相似文献   

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6.
The infrared and Raman spectra of cis- and trans-dimethylbromocyclopropane have been recorded from 4000 to 50 cm−1. An assignment of the majority of the fundamentals is proposed and compared to those of related molecules. Definite and consistent trends in a number of normal modes of the ring and the methyl groups with the nature, position and number of the substituents have been found. Clear evidence has been obtained for steric interaction between the three substituents in cis-position.  相似文献   

7.
Photochromism of 1,2-dimethyl-5-phenyl-3-pyrryl fulgide (compound I) has been investigated in various solvents. The photocyclization process of I has been examined by means of nanosecond time resolved absorption spectroscopy; a new transient species was found on the nanosecond time scale. Oxygen can severely quench the new transient species. The photocyclization process is shown to be complicated. Both the excited singlet state and the excited triplet state are involved in the photochromic process.  相似文献   

8.
4-Acyl-1,2-dimethyl-3H-phenothiazin-3-ones were prepared by the photochemical reaction of 1,2-dimethyl-3H-phenothiazin-3-one with aldehydes. The structures of the newly prepared compounds were determined by elemental analysis, spectroscopic methods (ir, nmr and ms) and comparison with a sample prepared by an alternate route.  相似文献   

9.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 856–857, June, 1989.  相似文献   

10.
Summary Unlike 2-(3,4-dihydro-6-methoxy-1-naphthyl)ethenol acetate (I) [4-(2-acetoxyvinyl)-1,2-dihydro-7-methoxy-naphthalene], the diene of analogous structure -1,2-dihydro-7-methoxy-4-vinylnaphthalene (III)-in condensation with 3,5-dimethyl-3-cyclopentene-1,2-dione (II) forms an adduct (IV) which contains a 15- and not a 17-keto group. The orientation in the diene condensation is determined by the presence, or absence, of an electronegative substituent in the 1-position of the diene of type (III).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1058–1061, June, 1965  相似文献   

11.
4,5-Dimethyl-1,2-dithiole-3-thione 1 reacts with primary amines and formaldehyde to give the mono-, retro-, bis-Mannich bases in moderate yield.  相似文献   

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Condensation of acetonylacetone with symmetrical dimethyl- and diethylhydrazines leads to 1,2-dialkyl-3,6-dimethyl-1,2-dihydropyridazines and 2,3,5,6-tetraalkyl-1,4-dimethyl-2, 3,5,6-tetraazabicyclo[2.2.2]octanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 400–403, March, 1971.  相似文献   

15.
染料敏化纳米薄膜太阳电池中DMPII浓度的优化   总被引:5,自引:0,他引:5  
利用超微铂电极和循环伏安法及电化学阻抗谱研究了在1,2-二甲基-3-丙基咪唑碘(DMPII)的3-甲氧基丙腈(MePN)溶液中I3和I的氧化还原行为,并对比了由不同浓度的I2和DMPII组成的电解质溶液,其染料敏化纳米薄膜太阳电池(DSCs)的光伏性能. 发现以MePN为溶剂,含1.0 mol•dm-3 DMPII、0.12 mol•dm-3 I2、0.10 mol•dm-3 LiI和0.50 mol•dm-3 4-叔丁基吡啶的电解质溶液,其DSCs的短路光电流密度为16.67 mA•cm-3、开路电压为0.69 V、填充因子为0.70、光电转换效率达8.08%.  相似文献   

16.
Salinas F  Diaz TG  Sanchez JC 《Talanta》1987,34(7):655-656
The iron (II)-5,5-dimethyl-1,2,3-cyclohexanetrione-1,2-dioxime-3-thiosemicarbazone complex can be extracted from a medium of high acidity into amyl alcohol. Measurement of the absorbance at 550 nm gives a determination limit for iron of 0.015 mu/ml. The method has been applied to the determination of iron in water, wine, beer and fruit juice.  相似文献   

17.
A novel, convenient method has been developed for the synthesis of 1,2-bis(2,5-dimethyl-3-thienyl)ethanedione, from which were prepared 5,6-bis(2,5-dimethyl-3-thienyl)-1,2,4-triazines (analogs of the photochromic 1,2-diarylethenes). The principial possibility of using 1,2,4-triazines obtained as photochromic agents was investigated.  相似文献   

18.
The interaction of the clinically used 1,2-dimethyl-3-hydroxypyrid-4-one with trivalent europium Eu(III), was investigated by using potentiometric and spectroscopic methods. The stability constants of the EuLn (3−n)+ complexes determined by spectroscopic and potentiometric measurements were found to be log β11 = 6.5±0.3 and log β12 = 12.0±0.5. However, at pH ≥ 5, hydrolysis of the Eu-L complexes starts, resulting in the formation of needle-type, yellow crystals. The low solubility of the Eu-L complexes in the neutral pH range is disadvantageous with respect to the use of deferiprone as chelating agent for decorporation of trivalent f-elements.  相似文献   

19.
1 INTRODUCTION Antipyrine (2,3-dimethyl-1-phenyl-5-pyrazolone) and its derivatives exhibit a wide range of biological activities and applications[1~3]. Antipyrine shows mi- nimal protein binding and is rapidly and complete- ly absorbed from the gastrointestinal tract and exten- sively metabolized by the cytochrome P450 liver en- zymes[4]. Estimates of half-life and systemic clear- ance of antipyrine have been used for the in vivo as- sessment of hepatic drug oxidation in different spe- c…  相似文献   

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