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31.
Anil K. Awasthi Santosh K. Upadhyay 《Monatshefte für Chemie / Chemical Monthly》1985,116(6-7):729-736
The kinetics of ruthenium(III) catalyzed oxidation of formaldehyde and acetaldehyde by alkaline hexacyanoferrate(III) has been studied spectrophotometrically. The rate of oxidation of formaldehyde is directly proportional to [Fe(CN)
3–
6
] while that of acetaldehyde is proportional tok[Fe(CN)
3–
6
]/{k +k[Fe(CN)
3–
6
]}, wherek, k andk are rate constants. The order of reaction in acetylaldehyde is unity while that in formaldehyde falls from 1 to 0. The rate of reaction is proportional to [Ru(III)]
T
in each case. A suitable mechanism is proposed and discussed.
Die Kinetik der Ru(III)-katalysierten Oxidation von Formaldehyd und Acetaldehyd mittels alkalischem Hexacyanoferrat(III)
Zusammenfassung Die Untersuchung der Kinetik erfolgte spektrophotometrisch. Die Geschwindigkeitskonstante der Oxidation von Formaldehyd ist direkt proportional zu [Fe(CN) 3– 6 ], währenddessen die entsprechende Konstante für Acetaldehyd proportional zuk[Fe(CN) 3– 6 ]/{k +k[Fe(CN) 3– 6 ]} ist, wobeik,k undk Geschwindigkeitskonstanten sind. Die Reaktionsordnung für Acetaldehyd ist eine erste, die für Formaldehyd fällt von erster bis zu nullter Ordnung. Die Geschwindigkeitskonstante ist in jedem Fall proportional zu [Ru(III)] T . Es wird ein passender Mechanismus vorgeschlagen.相似文献
32.
A regioselective quinazolinone-directed ortho lithiation on an adjacent quinoline moiety has been used as a key step for a short, efficient, and practical synthesis of the human DNA topoisomerase I poison luotonin A and luotonins B and E. The quinazolinoylquinoline 5 on treatment with in situ-generated nonnucleophilic mesityllithium furnished the desired dilithiated intermediate 6, which on treatment with formaldehyde followed by Mitsunobu ring closure reaction gave luotonin A (1a) in very good yield. The reaction of dilithiated intermediate 6 with DMF directly furnished luotonin B (1b) in 81% yield. Luotonin B (1b) on methylation with p-TSA/methanol gave luotonin E (1c) in 82% yield. 相似文献
33.
An inhibition effect of PdCl2 on the rate of oxidation of sugars by alkaline hexacyanoferrate(III) has been observed. The order of reactions in hexacyanoferrate(III) and OH− is zero and unity, respectively, while that in sugars decreases from unity at higher sugar concentration. The kinetic data and spectrophotometric evidence support the formation of {PdII − (sugar)} and {PdII − sugar)2} complexes and their resistance to react with Fe(CN)63− © 1996 John Wiley & Sons, Inc. 相似文献
34.
Dr. Santosh K. Nanda Dr. Rosy Mallik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(63):15571-15604
Oxygen-bearing motifs, mainly the congener heterocycles are ubiquitous due to their presence in various natural products and bioactive scaffolds. Although in literature, several strategies have been developed for their synthesis, hydroalkoxylation of alkynes has come forward as a method of choice and has been used extensively. In particular, hydroalkoxylation of alkynes has gained enormous attention from the synthetic community due to the rapid access to a very useful and reactive synthetic intermediate like ‘enol ether’. Furthermore, to manifold the utility of these methods, reports have been developed elaborating the generation of ‘enol ether’ using hydroalkoxylation and their usage in various reactions in cascade or tandem manner. This review focuses on recent development on the hydroalkoxylation of alkynes for the synthesis of oxygen-containing entities. 相似文献
35.
36.
Samir Kumar Sarkar Meenakshi Pegu Santosh Kumar Behera Siva Krishna Narra Pakkirisamy Thilagar 《化学:亚洲杂志》2019,14(24):4431-4431
37.
Sidhanath V. Bhosale Mohan B. Kalyankar Santosh V. Nalage Dattatry S. Bhosale Swati L. Pandhare Trupti V. Kotbagi 《合成通讯》2013,43(5):762-769
A simple one-pot synthesis has been developed for the synthesis of 2,4,5-trisubstituted imidazoles using an efficient and recyclable MoO3/SiO2 solid acid catalyst by condensation of benzil or benzoin, benzaldehyde, and ammonium acetate in acetonitrile as a solvent. Using this solid catalyst, the reactions could be carried out under mild reaction conditions with very good yield of imidazoles, up to 95%. This catalyst could be recycled very easily, which makes this methodology environmentally benign. 相似文献
38.
Summary The kinetics of the RuIII-catalyzed oxidation of the hydroxy acids; lactic, tartaric, malic and citric acids byN-bromosuccinimide in HClO4 and in the presence of Hg(OAc)2 have been studied. The reactions exhibit a first order rate dependence with respect to the oxidant and zeroth order rate dependence with respect to substrate. The rate is retarded by [H+], accelerated at law RuIII concentrations but independent of [RuIII] at higher RuIII concentrations. A mechanism consistent with the observed kinetic data is proposed. 相似文献
39.
Biranje Santosh Shivaji Sun Jianzhong Shi Yifei Yu Sujie Jiao Haixin Zhang Meng Wang Qianqian Wang Jin Liu Jun 《Cellulose (London, England)》2021,28(14):8899-8937
Cellulose - Excessive hemorrhage is a leading cause of death to trauma patients, especially in combat and civilian accidents. The main priority in the medical treatment of trauma patients is to... 相似文献
40.
Santosh Adhikari RaiAnna A. Hopson Bhishma R. Sedai Frederick M. McFarland Song Guo Toby L. Nelson 《Journal of polymer science. Part A, Polymer chemistry》2017,55(3):457-463
Four novel conjugated polymers containing the eumelanin‐inspired indole core have been successfully synthesized using common cross coupling reactions. These polymers differed by the arylene and the carbon–carbon bond linkage. Optoelectronic experiments of these polymers suggest that the ethynylene linkage contributed to the red‐shifted absorption spectra and blue‐shifted emission spectra when compared to the vinylene linkage polymers. Furthermore, the optical bandgaps of the poly(indoylenearyleneethynylene)s (PIAEs) were smaller compared to the poly(indoylenearylenevinylene)s (PIAVs). Surprisingly, the HOMOs of these polymers were less affected by the nature of the carbon–carbon linkage. However, the LUMOs of the PIAEs were lower in comparison to the PIAVs. These eumelanin‐inspired PIAEs and PIAVs are good fluorophores with fluorescence quantum yields ranging from 0.12 to 0.67 and have good thermal stability for applications such as in organic light‐emitting diodes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 457–463 相似文献