- Synthesis, Characterization, and Catalytic Reactivity of {CoNO}8PCP Pincer Complexes
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The reaction of coordinatively unsaturated Co(II) PCP pincer complexes with nitric oxide leads to the formation of new, air-stable, diamagnetic mono nitrosyl compounds. The synthesis and characterization of five- and four-coordinate Co(III) and Co(I) nitrosyl pincer complexes based on three different ligand scaffolds is described. Passing NO through a solution of [Co(PCPNMe-iPr)Cl], [Co(PCPO-iPr)Cl] or [Co(PCPCH2-iPr)Br] led to the formation of the low-spin complex [Co(PCP-iPr)(NO)X] with a strongly bent NO ligand. Treatment of the latter species with (X = Cl, Br) AgBF4 led to chloride abstraction and formation of cationic square-planar Co(I) complexes of the type [Co(PCP-iPr)(NO)]+ featuring a linear NO group. This reaction could be viewed as a formal two electron reduction of the metal center by the NO radical from Co(III) to Co(I), if NO is counted as NO+. Hence, these systems can be described as {CoNO}8 according to the Enemark-Feltham convention. X-ray structures, spectroscopic and electrochemical data of all nitrosyl complexes are presented. Preliminary studies show that [Co(PCPNMe-iPr)(NO)]+ catalyzes efficiently the reductive hydroboration of nitriles with pinacolborane (HBpin) forming an intermediate {CoNO}8 hydride species.
- Pecak, Jan,Eder, Wolfgang,St?ger, Berthold,Realista, Sara,Martinho, Paulo N.,Calhorda, Maria José,Linert, Wolfgang,Kirchner, Karl
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- Cobalt-Catalyzed Deoxygenative Hydroboration of Nitro Compounds and Applications to One-Pot Synthesis of Aldimines and Amides
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The commercially available and bench-stable Co(acac)2 ligated with bis[(2-diphenylphosphino)phenyl] ether (dpephos) was employed for selective room temperature hydroboration of nitro compounds with HBPin (TOF up to 4615 h?1), tolerating halide, hydroxy, amino, ether, ester, lactone, amide and heteroaromatic functionalities. These reactions offered a direct access to a variety of N-borylamines RN(H)BPin, which were in situ treated with aldehydes and carboxylic acids to produce a series of aldimines and secondary carboxamides without the need for dehydrating and/or coupling reagents. Combination of these transformations in a sequential one-pot manner allowed for direct and selective synthesis of aldimines and secondary carboxamides from readily available and inexpensive nitro compounds.
- Gudun, Kristina A.,Hayrapetyan, Davit,Khalimon, Andrey Y.,Segizbayev, Medet,Slamova, Ainur,Zakarina, Raikhan
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- Solvent-freeN-Boc deprotection byex situgeneration of hydrogen chloride gas
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An efficient, scalable and sustainable method for the quantitative deprotection of thetert-butyl carbamate (N-Boc) protecting group is described, using down to near-stoichiometric amounts of hydrogen chloride gas in solvent-free conditions. We demonstrate theex situgeneration of hydrogen chloride gas from sodium chloride and sulfuric acid in a two-chamber reactor, introducing a straightforward method for controlled and stoichiometric release of HCl gas. The solvent-free conditions allow deprotection of a wide variety ofN-Boc derivatives to obtain the hydrochloride salts in quantitative yields. The procedure obviates the need for any work-up or purification steps providing an uncomplicated green alternative to standard methods. Due to the solvent-free, anhydrous conditions, this method shows high tolerance towards acid sensitive functional groups and furnishes expanded functional group orthogonality.
- De Borggraeve, Wim M.,Gilles, Philippe,Van Mileghem, Seger,Verschueren, Rik H.
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supporting information
p. 5782 - 5787
(2021/07/12)
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- Discovery of Novel Dual-Target Inhibitor of Bromodomain-Containing Protein 4/Casein Kinase 2 Inducing Apoptosis and Autophagy-Associated Cell Death for Triple-Negative Breast Cancer Therapy
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Bromodomain-containing protein 4 (BRD4) is an attractive epigenetic target in human cancers. Inhibiting the phosphorylation of BRD4 by casein kinase 2 (CK2) is a potential strategy to overcome drug resistance in cancer therapy. The present study describes the synthesis of multiple BRD4–CK2 dual inhibitors based on rational drug design, structure–activity relationship, and in vitro and in vivo evaluations, and 44e was identified to possess potent and balanced activities against BRD4 (IC50 = 180 nM) and CK2 (IC50 = 230 nM). In vitro experiments show that 44e could inhibit the proliferation and induce apoptosis and autophagy-associated cell death of MDA-MB-231 and MDA-MB-468 cells. In two in vivo xenograft mouse models, 44e displays potent anticancer activity without obvious toxicities. Taken together, we successfully synthesized the first highly effective BRD4–CK2 dual inhibitor, which is expected to be an attractive therapeutic strategy for triple-negative breast cancer (TNBC).
- Chen, Juncheng,Chiang, Cheng-Ming,He, Gu,Liu, Bo,Liu, Jie,Ouyang, Liang,Tang, Pan,Wang, Guan,Yang, Chengcan,Ye, Tinghong,Zhang, Jifa,Zhang, Jin,Zou, Ling
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p. 18025 - 18053
(2022/01/03)
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- Sustainable organophosphorus-catalysed Staudinger reduction
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A highly efficient and sustainable catalytic Staudinger reduction for the conversion of organic azides to amines in excellent yields has been developed. The reaction displays excellent functional group tolerance to functionalities that are otherwise prone to reduction, such as sulfones, esters, amides, ketones, nitriles, alkenes, and benzyl ethers. The green nature of the reaction is exemplified by the use of PMHS, CPME, and a lack of column chromatography.
- Lenstra, Danny C.,Lenting, Peter E.,Mecinovi?, Jasmin
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supporting information
p. 4418 - 4422
(2018/10/17)
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- Direct cycle between co-product and reactant: An approach to improve the atom economy and its application in the synthesis and protection of primary amines
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Two important goals of green chemistry are to maximize the efficiency of reactants and to minimize the production of waste. In this study, a novel approach to improve the atom economy of a chemical process was developed by incorporating a direct cycle between a co-product and a reactant of the same reaction. To demonstrate this concept, recoverable 3,4-diphenylmaleic anhydride (1) was designed and used for the atom-economical synthesis of aliphatic primary amines from aqueous ammonia. In each individual cycle, only ammonia and alkyl halide were consumed, and 1 was recovered in nearly a quantitative yield. In this approach for developing atom-economical protecting agents, 1 showed good performance as a recoverable protecting agent for primary amines. The broad substrate scope, good tolerance to various reaction conditions, and high reaction and recovery rates make 1 a valuable complement to conventional primary amine protecting agents.
- Guan, Qi,Jiang, Mingyang,Wu, Junhui,Zhai, Yanpeng,Wu, Yue,Bao, Kai,Zhang, Weige
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supporting information
p. 5794 - 5799
(2016/11/06)
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- Reversible capture and release of aromatic amines by vicinal tricarbonyl compound
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In this paper, we report reversible capture and release of aromatic amines by diphenylpropanetrione (DPPT). Addition of aromatic amines to the central carbonyl group occurred readily at ambient temperature to provide the aromatic amine adducts of DPPT (DPPT-aromatic amines), which has a hemiaminal structure. On the other hand, washing a solution of DPPT-aromatic amine with diluted hydrochloric acid (HCl) enabled successful recovery of DPPT to demonstrate the reversible nature of this system.
- Yuki, Tatsuya,Yonekawa, Morio,Furusho, Yoshio,Sei, Yoshihisa,Tomita, Ikuyoshi,Endo, Takeshi
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p. 2868 - 2873
(2016/05/19)
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- High graphite N content in nitrogen-doped graphene as an efficient metal-free catalyst for reduction of nitroarenes in water
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Four kinds of nitrogen-doped graphene (NG) as metal-free catalysts are synthesized by a one-step hydrothermal reaction and thermal treatment using graphene oxide and urea as precursors. It is found that the reduction of nitroarenes can be catalyzed by using a low NG loading and a small amount of NaBH4 in water with high yield. The type of nitrogen species in NG has an important effect on the reduction reaction. The NG catalyst containing the most graphite N shows the highest catalytic activity during reduction of nitroarenes, which demonstrates that the graphite N of NG plays a key role in impelling this reaction. The reaction mechanism is proven by GC-MS experiments, and DFT calculations reveal the reasons for the graphite N showing better catalytic activity. It is worth noting that no dehalogenation phenomenon occurs during the reduction process for halogen-substituted nitroarenes in contrast to conventional metal catalysts. In addition, the NG catalyst can be simply recycled and efficiently used for eight consecutive runs with no significant decrease in activity.
- Yang, Fan,Chi, Cheng,Wang, Chunxia,Wang, Ying,Li, Yongfeng
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supporting information
p. 4254 - 4262
(2016/08/02)
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- The ortho effect on the acidic and alkaline hydrolysis of substituted formanilides
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The kinetics of formanilides hydrolysis were determined under first-order conditions in hydrochloric acid (0.01-8 M, 20-60°C) and in hydroxide solutions (0.01-3 M, 25 and 40°C). Under acidic conditions, second-order specific acid catalytic constants were used to construct Hammett plots. The ortho effect was analyzed using the Fujita-Nishioka method. In alkaline solutions, hydrolysis displayed both first- and second-order dependence in the hydroxide concentration. The specific base catalytic constants were used to construct Hammett plots. Ortho effects were evaluated for the first-order dependence on the hydroxide concentration. Formanilide hydrolyzes in acidic solutions by specific acid catalysis, and the kinetic study results were consistent with the AAC2 mechanism. Ortho substitution led to a decrease in the rates of reaction due to steric inhibition of resonance, retardation due to steric bulk, and through space interactions. The primary hydrolytic pathway in alkaline solutions was consistent with a modified BAC2 mechanism. The Hammett plots for hydrolysis of meta- and para-substituted formanilides in 0.10 M sodium hydroxide solutions did not show substituent effects; however, ortho substitution led to a decrease in rate constants proportional to the steric bulk of the substituent.
- Desai, Salil Dileep,Kirsch, Lee E.
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p. 471 - 488
(2015/06/30)
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- Synthesis, cytotoxic evaluation, and in silico studies of substituted N-alkylbromo-benzothiazoles
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In efforts to develop a new class of anticancer agents with improved efficacy and selective action, a series of N-alkylbromo-benzothiazoles were synthesized and evaluated for in vitro cytotoxic activity against various human cancer cell lines such as lung (A-549), prostate (PC-3), leukemia (THP-1), and colon (Caco-2). They were found to be highly active against prostate (PC-3) and leukemia (THP-1) cancer cells, moderately active against colon (Caco-2) cancer cells and less active against lung (A-549) cancer cells. Of the 12 compounds, two (11d, 11j) exhibit IC50 values of ≤ 1 μM against leukemia (THP-1) cancer cell lines. Compound 11l showed significant cytotoxic activity against the PC-3 (IC50 = 0.6 μM), THP-1 (IC50 = 3 μM) and Caco-2 cell lines (IC50 = 9.9 μM), respectively. Docking study of the synthesized ligand was done on epidermal growth factor receptor using ArgusLab flexible docking, to determine their observed activity. Further QSAR investigations with stepwise multiple linear regression analysis were applied to find correlation between various physicochemical parameters and anticancer activity. The QSAR results showed that anticancer activity could be modeled with descriptors. The predictive ability of models was cross-validated by observation of the low residual activity values and adjusted coefficient of variation (radj2) obtained by leave-one-out technique.
- Gill, Rupinder Kaur,Singh, Gagandeep,Sharma, Anuradha,Bedi,Saxena
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p. 4211 - 4222
(2013/09/02)
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- A facile and efficient method for the selective deacylation of N-arylacetamides and 2-chloro-Narylacetamides catalyzed by SOCl2
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Thionyl chloride efficiently and selectively promoted the deacylation of N-arylacetamides and 2-chloro-N-arylacetamides, under anhydrous conditions, without effecting the ester group, aminosulfonyl group, or benzyloxyamide group. This method, which has been successfully applied to a variety of substrates including different N-arylacetamides and 2-chloro-N-arylacetamides, has the attractive advantages of inexpensive reagents, satisfactory selectivity, excellent yields, short reaction time, and convenient workup. This new method can probably be used to selectively deacylate between aromatic amides and alkyl amides. Springer Science+Business Media B.V. 2011.
- Wang, Gong-Bao,Wang, Lin-Fa,Li, Chao-Zhang,Sun, Jing,Zhou, Guang-Ming,Yang, Da-Cheng
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experimental part
p. 77 - 89
(2012/05/20)
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- Bromination and diazo-coupling of pyridinethiones; microwave assisted synthesis of isothiazolopyridine, pyridothiazine and pyridothiazepines
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Isothiazolopyridines, pyridothiazines and pyridothiazepines are important compounds that possess valuable biological activities. This paper reports on the synthesis of these compounds using both conventional chemical methods and modern microwave techniques. 3-Bromo-6-hydroxy-4-methyl-2-thioxo-2,3- dihydropyridine-3-carboxamide, 5-arylazo-6-hydroxy-4-methyl-2-thioxo-1,2- dihydropyridine-3-carboxamides, 3,5-bis-arylazo-6-hydroxy-4-methyl-2-thioxo-2,3- dihydropyridine-3-caboxamide, 4-methyl-2,3,6,7-tetrahydroisothiazolo[5,4-b]- pyridine-3,6-dione, 2,2'-(methylene-bis-(sulfanediyl))bis(4-methyl-6-oxo-1,6- dihydropyridine-3-carboxamide), 2-hydroxy-5-methyl-4H-pyrido[3,2-e][1,3]- thiazine-4,7(8H)-dione and 2-arylmethylene-8-hydroxy-6-methyl-2,3,4,5- tetrahydropyrido-[3,2-f][1,4]thiazepine-3,5-diones have been prepared from 6-hydroxy-4-methyl-2-thioxo-2,3-dihydropyridine-3-carboxamide. Some of these compounds were prepared using microwave-assisted reaction conditions, that provided higher yields in shorter times than the conventional methods.
- Youssef, Ayman M. S.,Azab, Mohamed E.,Youssef, Mohamed M.
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experimental part
p. 6930 - 6943
(2012/09/07)
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- Kinetics and mechanism of the anilinolysis of dicyclohexyl phosphinic chloride in acetonitrile
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The nucleophilic substitution reactions of dicyclohexyl phosphinic chloride [3; cHex2P(=O)Cl] with substituted anilines (XC6H 4NH2) and deuterated anilines (XC6H 4ND2) are investigated kinetically in acetonitrile at 60.0 °C. The anilinolysis rate is too slow to be rationalized by the stereoelectronic effects. The rate is contrary to expectations for the electronic influence of the two ligands and exhibits exceptionally great negative deviation from the Taft's eq. The deuterium kinetic isotope effects (DKIEs) involving deuterated anilines invariably change from primary normal (kH/kD > 1; max kH/kDt = 1.10 with X = 4-MeO) with the strongly basic anilines (X = 4-MeO, 4-Me, 3-Me) to secondary inverse (kH/kDt H/k Dt = 0.673 with X = 3-Cl) with the weakly basic anilines (X = H, 4-F, 4-Cl, 3-Cl). A concerted SN2 mechanism is proposed on the basis of both secondary inverse and primary normal DKIEs. The obtained DKIEs imply that the fraction of a frontside attack increases as the aniline becomes more basic. A hydrogen-bonded, four-center-type transition state is suggested for a frontside attack, while the trigonal bipyramidal pentacoordinate transition state is suggested for a backside attack.
- Ul Hoque, Md. Ehtesham,Lee, Hai Whang
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experimental part
p. 1997 - 2002
(2012/02/01)
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- New method for the direct electrophilic amination of aromatic compounds and its use in the annelation of the pyrimidine ring
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A method has been developed for the synthesis of aromatic amines by the amination of the corresponding aromatic compounds using sodium azide in PPA. A method for the synthesis of quinazolines and benzo[h]quinazolines using this reaction and the subsequent reaction of the intermediates with 1,3,5-triazines has been developed.
- Aksenov,Lyakhovnenko,Kugutov
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p. 1262 - 1265
(2011/10/09)
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- Alternative method for the reduction of aromatic nitro to amine using TMDS-iron catalyst system
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The system 1,1,3,3-tetramethyldisiloxane (TMDS)/Fe(acac)3 is reported here as a new method to obtain amines from aromatic nitro compounds. Amines are synthetized in a straightforward step and are isolated as hydrochloride salts with good to excellent yields. This system has shown a good selectivity toward aryl-chloride, aryl-bromide, ester, carboxylic acid, and cyano groups. The reduction of alkylnitro compounds was unfortunately not possible using this method, only a mixture of mono and dialkylated amine was obtained.
- Pehlivan, Leyla,Métay, Estelle,Laval, Stéphane,Dayoub, Wissam,Demonchaux, Patrice,Mignani, Gérard,Lemaire, Marc
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experimental part
p. 1971 - 1976
(2011/04/22)
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- EPR and ENDOR spectroscopic study of the reactions of aromatic azides with gallium trichloride
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The reactions of gallium trichloride with phenyl and deuterio-phenyl azides, as well as with 4-methoxyphenyl azide and deuterium isotopomers, were examined by product analysis, CW EPR spectroscopy and pulsed ENDOR spectroscopy. The products included the corresponding anilines together with 4-aminodiphenylamine type dimers, and polyanilines. Complex CW EPR spectra of the radical cations of the dimers [ArNHC6H4NH 2]+ and trimers [ArNHC6H4NHC 6H4NH2]+ were obtained. These EPR spectra were analysed with the help of data from the deuterium-substituted analogues as well as the pulse Davies ENDOR spectra. DFT computations of the radical cations provided corroborating evidence and suggested the unpaired electrons were accommodated in extensive π-delocalised orbitals. A mechanism to account for the reductive conversion of aromatic azides to the corresponding anilines and thence to the dimers and trimers is proposed.
- Bencivenni, Giorgio,Cesari, Riccardo,Nanni, Daniele,El Mkami, Hassane,Walton, John C.
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supporting information; experimental part
p. 5097 - 5104
(2010/12/24)
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- Concurrent primary and secondary deuterium kinetic isotope effects in anilinolysis of O-aryl methyl phosphonochloridothioates
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The nucleophilic substitution reactions of Y-O-aryl methyl phosphonochloridothioates with substituted anilines (XC6H 4NH2) and deuterated anilines (XC6H 4ND2) are investigated kinetically in acetonitrile at 55.0°C. The Hammett and Bronsted plots for substituent (X) variations in the nucleophiles are biphasic concave downwards with a break region between X = H and 4-Cl. The deuterium kinetic isotope effects (DKIEs) are primary normal (kH/kD = 1.03-1.30) for stronger nucleophiles (X = 4-MeO, 4-Me and H), and extremely large secondary inverse (kH/kD = 0.367-0.567) for weaker nucleophiles (X = 4-Cl, 3-Cl and 3-NO2). The cross-interaction constants are negative (ρXY(H) = -0.95 and ρXY(D) = -1.11) for stronger nucleophiles, while positive (ρXY(H) = +0.77 and ρXY(D) = +0.21) for weaker nucleophiles. These kinetic results indicate that the mechanism changes from a concerted process involving frontside nucleophilic attack for stronger nucleophiles to a stepwise process with a rate-limiting leaving group expulsion from the intermediate involving backside attack for weaker nucleophiles. A hydrogen-bonded, four-center-type transition state (TS) is suggested for a frontside attack, while a trigonal bipyramidal pentacoordinate TS is suggested for a backside attack. The unusually small DKIEs, as small as or equal to 0.4, for weaker nucleophiles seem to be ascribed to severe steric congestion in the TS.
- Ul Hoque, Md. Ehtesham,Guha, Arun Kanti,Kim, Chan Kyung,Lee, Bon-Su,Lee, Hai Whang
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experimental part
p. 2919 - 2925
(2011/02/28)
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- Kinetics and mechanism of the aminolysis of dimethyl and methyl phenyl phosphinic chlorides with anilines
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The reactions of dimethyl phosphinic chloride (1) and methyl phenyl phosphinic chloride (2) with X-anilines have been studied kinetically in acetonitrile at 15.0 and 55.0 °C, respectively. The deuterium kinetic isotope effects (KIEs) involving deuterated aniline nucleophiles (XC 6H4ND2) are also reported for the same reactions. The obtained KIEs for 1 are secondary inverse (kH/k D=0.703-0.899H/kD=1.62-2.10> 1). A concerted mechanism involving predominantly backside nucleophilic attack is proposed for the anilinolysis of 1. A concerted mechanism involving predominantly frontside attack via a hydrogen-bonded four-center-type transition state is proposed for the anilinolysis of 2. The degree of steric hindrance is the major factor that determines both the reactivity of the phosphinates and the direction of the nucleophilic attack on the phosphinates. Copyright
- Dey, Nilay Kumar,Hoque, Md. Ehtesham Ul,Kim, Chan Kyung,Lee, Bon-Su,Lee, Hai Whang
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experimental part
p. 425 - 430
(2010/04/30)
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- Studies with azinylacetonitriles: 2-Pyridylacetonitrile as a precursor to functionally substituted pyridines
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2-Pyridylacetonitrile (1) couples with aromatic diazonium salts to yield arylhydrazones 2a-c, that were shown to exist in the syn-form 2 rather than the anti-form 4. Compounds 2a,c reacted with hydroxylamine in refluxing DMF to yield the interesting 1,2,3-triazolylpyridines 6. Attempts to cyclize 2 to give the corresponding fused pyrazolopyridines 9 failed. On the other hand, compound 1 condensed with dimethylformamide dimethyl acetal to yield enaminonitrile 10 that could be converted into pyrazolylpyridine 11.
- Al-Sheikh, Mariam Abdullah,Elnagdi, Mohamed Hilmy
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experimental part
p. 4406 - 4413
(2010/04/24)
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- Synthesis of primary amines by the electrophilic amination of Grignard reagents with 1,3-dioxolan-2-one O-sulfonyloxime
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(Chemical equation presented) Primary amines are prepared by the electrophilic amination of Grignard reagents with 4,4,5,5-tetramethyl-1,3- dioxolan-2-one O-phenylsulfonyloxime and the acidic hydrolysis of the resulting imines.
- Kitamura, Mitsuru,Suga, Takahiro,Chiba, Shunsuke,Narasaka, Koichi
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p. 4619 - 4621
(2007/10/03)
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- Acetyl chloride-methanol as a convenient reagent for: A) quantitative formation of amine hydrochlorides; B) carboxylate ester formation; C) mild removal of N-t-Boc-protective group
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Hydrogen chloride quatitativaly generated in situ by the addition of acetyl chloride to alcoholic solutions is a useful reagent for carboxylic acid esterification, N-t-Boc deprotection and phosphoramide solvolysis reactions.
- Nudelman, Ayelet,Bechor, Yosi,Falb, Eliezer,Fischer, Bilha,Wexler, Barry A.,Nudelman, Abraham
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p. 471 - 474
(2007/10/03)
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- NUCLEOPHILIC SUBSTITUTION REACTIONS OF CUMYL CHLORIDES IN METHANOL
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Nucleophilic substitution reactions of cumyl chlorides with anilines in methanol have been investigated.Large negative ρY+ values in methanol and weak chloride common ion rate depression support a mechanism in which a preformed benzylic-type carbocation intermediate reacts with the solvent and the added nucleophile, aniline.All positive ρX (ρnuc) values observed and the estimated non-interactive point, ?Y+ = 0.72, strongly suggest that deprotonation of a mobile proton from the nucleophile occurs during the reaction.Fair linear correlation is exhibited for the plot of stability of carbocation, as expressed by the enthalpy of cation formation (AM1), and ?Y+, indicating that the thermodynamic driving force is nearly compensated for by the intrinsic barrier.
- Lee, Ikchoon,Koh, Han Joong,Hong, Sung Nam,Lee, Bon-Su
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p. 347 - 352
(2007/10/02)
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- EFFECT OF THE STRUCTURE ON THE RATE OF THE REACTIONS OF AROYL CHLORIDES WITH PRIMARY ARYLAMINES IN MIXTURES OF tert-BUTYL ALCOHOL AND CHLOROBENZENES. THE TRANSITION THROUGH ISOPARAMETRIC POINTS WITH RESPECT TO THE STRUCTURE PARAMETERS
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The rate of the reactions of aroyl chlorides with primary arylamines in 3.5, 5, and 7M solutions of tert-butyl alcohol in chlorobenzene at 25 deg C was measured.The effect of the structure of the reagents on the process rate was determined quantitatively by means of the Hammett-Taft and crossed correlation equations.The isoparametric points with respect to the structure of the substrate and the nucleophile were reached experimentally, and the transition through some of these points was also realised.It was found that the specific solvation of the primary arylamines by the tert-butyl alcohol was nonuniform in that an incre ase in the concentration of the alcohol in the investigated range reduced, did not change, and increased the rates of the reactions with 3-chloroaniline, 3-nitroaniline, and 3-nitro-5-methoxycarbonylaniline respectively.The effect of specific solvation on the behavior of the correlation parameters is discussed.
- Shpan'ko, I. V.,Likhomanenko, E. E.
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p. 1702 - 1710
(2007/10/02)
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- Dye lasers using 2-(4-pyridyl)-5-aryloxazoles and quaternary salts of these compounds
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2-(4-pyridyl)-5-aryloxazoles and certain quaternary salts of these compounds are useful as visible-wavelength lasing dyes. These dyes are used in solution with non-interferring polar solvents, such as low molecular weight alcohols, H2 O, and D2 O, to form lasing media useful in dye lasers. Such lasers generally include a reservoir for containing the laser dye solution and a pumping energy source operably coupled therewith for producing stimulated emission of the dye solution.
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