- Stability indicating spectrophotometric methods for quantitative determination of carbamazepine and its degradation product, iminostilbene, in pure form and pharmaceutical formulations
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A stressed study on the stability and degradation behavior under ICH forced degradation conditions of most widely used antiepileptic drug; carbamazepine (CMZ) is presented in this work. The research also includes studying spectrophotometric nature of CMZ and assaying it with mostly used spectrophotometric techniques. Six simple and sensitive spectrophotometric methods are introduced as stability indicating methods for quantitative determination of CMZ and its degradation product, one of its reported potential impurities; iminostilbene (IMS). Dual wavelength is method I where two wavelengths (215 and 270 nm for CMZ and 258 and 307 nm for IMS) were chosen for each component while absorbance difference is zero for the second one. Method II is isoabsorptive point method where the absorbance of CMZ at A225 nm was measured in the range of 0.5–20 μg mL?1. Method III is second derivative method which allows simultaneous determination of CMZ at 247 nm and IMS at 273 nm without any interference. Method IV based on measuring the peak amplitude of first derivative of ratio spectra (1DD) at 280.5 and 253 nm for determination of CMZ and IMS, respectively. Method V is mean centering of the ratio spectra with good linearity for CMZ and IMS over 200–330 nm. Ratio difference method is method VI where good linearity was achieved for determination of CMZ and IMS by measuring differences in the amplitude of ratio spectra at 285, 258 nm and 258, 285 nm, respectively. The proposed methods show successful application in CMZ's pharmaceutical formulations.
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Read Online
- High temperature polymorphic conversion of carbamazepine in supercritical CO2: A way to obtain pure polymorph I
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In this work, we studied the high-temperature polymorphic conversion of carbamazepine (CBZ) in a high-density supercritical CO2 (scCO2) medium in the temperature range of 110–200°C. In order to understand the mechanism of transformation we performed a detailed IR analysis of the supercritical fluid (SCF) phase being in permanent contact with an excess of CBZ. We studied the conformational equilibrium of CBZ molecules in scCO2 phase under isochoric heating conditions. Three temperature ranges, where different types of CBZ–scCO2 equilibria are realized, were considered: i. ?CBZ solid – SCF solution?; ii. phase transition region related to the melting of CBZ in high-density scCO2; iii. ?CBZ melt – SCF solution?. An analysis of the IR spectroscopy data on CBZ dissolved in the scCO2 phase obtained for the third temperature range shows that when ?CBZ melt – SCF solution? equilibrium exists, the scCO2 phase contains only one CBZ conformer. Relying on this finding, we hypothesized that it is possible to obtain pure CBZ polymorph I by the crystallization from CBZ solution in scCO2. This statement has been proven by the micro-Raman analysis of the crystalline substance being obtained from such fluid solution.
- Oparin, Roman D.,Vaksler, Yevhenii A.,Krestyaninov, Michael A.,Idrissi, Abdenacer,Kiselev, Michael G.
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Read Online
- Method for synthesizing iminostilbene
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The invention discloses a method for synthesizing iminostilbene, which comprises the following steps: by using 1-phenylindole as a starting raw material, carrying out intramolecular rearrangement reaction on 1-phenylindole under the action of a composite acidic catalytic system to generate iminostilbene; wherein the composite acidic catalytic system is formed by mixing a phosphorus-containing acidic substance and a sulfur-containing acidic substance, the phosphorus-containing acidic substance is one or more of polyphosphoric acid, phosphoric acid and phosphorus pentoxide, and the sulfur-containing acidic substance is one or more of sulfuric acid, methanesulfonic acid and p-toluenesulfonic acid. The phosphorus-containing acidic substance and sulfur-containing acidic substance are used together to form the composite acidic catalytic system, the catalytic system is used in a reaction for catalytic synthesis of iminostilbene, corresponding reaction conditions are optimized, reaction time is shortened, side reactions are reduced, and therefore the method has the advantages of being high in product yield, short in reaction time and the like. The highest yield of the product reaches 83.4%, the purity is 99%, and a good technical effect is achieved.
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Paragraph 0018-0033
(2021/03/11)
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- Combined KOH/BEt3Catalyst for Selective Deaminative Hydroboration of Aromatic Carboxamides for Construction of Luminophores
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The selective catalytic C-N bond cleavage of amides into value-added amine products is a desirable but challenging transformation. Molecules containing iminodibenzyl motifs are prevalent in pharmaceutical molecules and functional materials. Here we established a combined KOH/BEt3 catalyst for deaminative hydroboration of acyl-iminodibenzyl derivatives, including nonheterocyclic carboxamides, to the corresponding amines. This novel transition-metal-free methodology was also applied to the construction of Clomipramine and luminophores.
- Li, Jinshan,Wang, Jiali,Yang, Jianguo,Yao, Wubing,Zhong, Aiguo
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supporting information
p. 8086 - 8090
(2020/11/03)
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- Chemical synthesis, spectroscopic studies, chemical reactivity properties and bioactivity scores of an azepin-based molecule
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Azepines derived molecules are of great interest because of their multi-drug like properties and thus advantageous in biomedical field. Herein, a novel route is described for the synthesis of an azepine-based molecule, 10,11-Dibromo-10,11-dihydro- 5H-dibenzo[b,f]azepine-5-carbonyl chloride (DACC) by using dibutyltin dilaurate (DBTDL) as catalyst. The structure of DACC was elucidated by using FT-IR, NMR, and mass spectroscopic techniques. Several density functionals were considered for the study of the molecular properties of the synthesized compound. The global and local reactivity descriptors were estimated by using Conceptual Density Functional Theory (CDFT). The active sites suitable for the nucleophilic and electrophilic attacks were selected by linking them with the Fukui indices, Parr functions and condensed Dual Descriptor Δf(r). Finally, the bioactivity scores for the studied molecule were predicted through different methodologies.
- Kollur, Shiva Prasad,Castro, Joaquín Ortega,Frau, Juan,Glossman-Mitnik, Daniel
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p. 300 - 306
(2018/12/13)
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- Intermediate compound, carbamazepine and derivative thereof as well as preparation method of oxcarbazepine and derivative thereof
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The invention provides an intermediate compound, carbamazepine and a derivative thereof as well as a preparation method of oxcarbazepine and a derivative thereof. 2-substituted aminophenylacetate or 2-substituted aminophenylacetonitrile and 2-halobenzonitrile are used as raw materials, substitution reaction, intramolecular condensation reaction, hydrolysis and hydrochloric acid acidification are carried out to obtain the oxcarbazepine and the derivative 5-substituent-10-oxa-10, 11-dihydro-5H-dibenzo [b, f] aza thereof, and the derivative of the oxcarbazepine can be used as a raw material to prepare the carbamazepine and the derivative 5-substituted iminostilbene thereof, an intermediate compound iminostilbene and intermediate compounds 5-substituted-10-methoxyiminostilbene and 10-methoxyiminostilbene. The raw materials used in the method are cheap and easy to obtain, and the cost is low; the preparation method is simple, conditions are easy to realize, the method is simple, convenientand safe to operate, and the process flow is short; the production amount of three wastes is small, and thus, the method is environmentally friendly; and a target product has high yield and purity, and is suitable for industrial production.
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Paragraph 0134; 0135
(2019/12/25)
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- Hydride-catalyzed selectively reductive cleavage of unactivated tertiary amides using hydrosilane
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The first hydride-catalyzed reductive cleavage of various unactivated tertiary amides, including the biologically active aryl-phenazine carboxamides and the challenging non-heterocyclic carbonyl functions, using low-cost hydrosilane as a reducing reagent has been developed. The novel catalyst system exhibits high efficiency and exclusive selectivity, providing the desired amines in useful to excellent yields under mild conditions. Overall, this transition metal-free process may offer a versatile alternative to currently employed expensive reducing reagents, high-pressure hydrogen or metal systems for the selective reductive cleavage of amides.
- Yao, Wubing,Li, Rongrong,Yang, Jianguo,Hao, Feiyue
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p. 3874 - 3878
(2019/08/07)
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- A disubstituted amide derivatives decarbonylation hydrogenation green new method (by machine translation)
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The invention relates to a high efficiency, high selectivity of the disubstituted amide derivatives of decarbonylation hydrogenation reaction green new method. For the first time to the metallic compound triethylborane as catalyst, under mild conditions can be conveniently catalytic N, N - di-aryl substituted amide and its derivative and cheap and easy to obtain organic silicon reagent selective preparation of secondary organic amine product. Compared with the traditional method, the new method generally has the wide substrate universality, functional group compatibility outstanding, simple operation and the like. For the first time in order to realize the organic silicon reagent as reducing agent and amide compounds decarbonylation hydrogenation reaction, is the reduction of amides and derivatives thereof, in particular the organic light-emitting diodes (OLEDs) material unit - diaryl amine compound of the laboratory preparation or industrial production provides a brand-new "green" response strategies. (by machine translation)
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Paragraph 0038; 0039; 0040; 0041
(2018/02/04)
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- One-step synthesis method of iminostilbene
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The invention discloses a one-step synthesis method of iminostilbene, and belongs to the field of drug synthesis. Under the argon protection condition, 2-aminostilbene is added; under the stirring condition, the temperature is slowly increased to 100-105 DEG C, at the moment, 2-aminostilbene is molten, anhydrous phosphorus acid is slowly dropped, after dropping is complete, the temperature is increased to continue the reaction, after the reaction is completed, the product is poured into an ice-water mixture, a 10% sodium hydroxide solution is used for adjusting the pH to be neutral, filtering is performed, a filtrate is extracted through dichloromethane, organic layers are combined and washed three times through saturated salt solutions and water, the organic layers are dried through anhydrous magnesium sulfate, filtering is performed, decompression and rotary evaporation are performed, and dichloromethane is recycled to obtain iminostilbene. According to the method, many defects in the prior art are overcome, iminostilbene can be obtained through the one-step reaction, the yield reaches 95% or above, and a solvent can be recycled. According to the synthesis method of iminostilbene, the iminostilbene synthesis cost can be greatly lowered on the whole, and the industrial application prospect is achieved.
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Paragraph 0016; 0017; 0018; 0019; 0020; 0021
(2017/05/06)
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- Convenient syntheses of halo-dibenz[b,f]azepines and carbamazepine analogues via N-arylindoles
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The dibenz[b,f]azepine heterocyclic system and related molecules with a single 10,11-bond are important templates for well-prescribed drug molecules, notably carbamazepine (anticonvulsant), clomipramine and imipramine (antidepressants). We synthesised a range of halogenated carbamazepine analogues, in connection with metabolic and immunological studies, as probes for structure-metabolism and hypersensitive effects and have published on their metabolic behaviour. While a number of synthetic routes to such analogues are possible, we naturally sought short and efficient methods for our target compounds. In the following report we present an effective two-step synthesis of a range of dibenz[b,f]azepines from appropriate indoles via N-arylation, then acid-catalysed rearrangement, with a critical analysis of other approaches. We showed earlier that this route was effective for fluoro analogues and here present a broader review of its scope. The 5-(carboxamido) side chain of carbamazepine may be added in various ways, affording overall a convenient access to drug molecules.
- Elliott, Emma-Claire,Maggs, James L.,Park, B. Kevin,O'Neill, Paul M.,Stachulski, Andrew V.
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p. 8426 - 8434
(2013/12/04)
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- An efficient synthesis for eslicarbazepine acetate, oxcarbazepine, and carbamazepine
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Efficient methods have been developed for the synthesis of three active pharmaceutical ingredients (APIs) carbamazepine (Tegretol) 1, oxcarbazepine (Trileptal) 2, and eslicarbazepine acetate (Exalief) 3 by employing enantioselective reduction and carboxamidation reaction.
- Ravinder,Rajeshwar Reddy,Sridhar,Murali Mohan,Srinivas, Katkam,Panasa Reddy,Bandichhor, Rakeshwar
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supporting information
p. 2841 - 2844
(2013/06/26)
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- Auto-tandem catalysis: Synthesis of acridines by Pd-catalyzed C=C bond formation and C(sp2)-N cross-coupling
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A facile palladium-catalyzed synthesis of acridines has been realized by consecutive C=C double bond formation and C-N cross-coupling. A variety of functionalized acridines can be accessed from easily available o-dihalobenzenes and N-tosylhydrazones in a single operation. This one-pot protocol has a wide scope with respect to both coupling partners, and provides an efficient route to functionalized acridine derivatives, which are generally difficult to synthesize by previously known methods.
- Huang, Zhongxing,Yang, Yang,Xiao, Qing,Zhang, Yan,Wang, Jianbo
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supporting information
p. 6586 - 6593
(2013/01/15)
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- Palladium-catalyzed reaction of aryl iodides with ortho-bromoanilines and norbornene/norbornadiene: Unexpected formation of dibenzoazepine derivatives
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Expecting the unexpected: The title reaction leads to satisfactory yields of dihydrodibenzoazepines 1-a from norbornene. The dibenzoazepines 2 can also be accessed from compounds of type 1-b when norbornadiene is used as a reactant. Theoretical studies show that the reaction represents a chelation-driven deviation from the usual selectivity observed in the presence of ortho-substituents on the aryl iodide.
- Della Ca', Nicola,Maestri, Giovanni,Malacria, Max,Derat, Etienne,Catellani, Marta
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p. 12257 - 12261
(2012/01/19)
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- Synthesis of heterocycles via Pd-ligand controlled cyclization of 2-chloro-N-(2-vinyl)aniline: Preparation of carbazoles, indoles, dibenzazepines, and acridines
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The Pd-catalyzed condensation of 2-bromostyrene and 2-chloroaniline derivatives yields stable diphenylamine intermediates, which are selectively converted to five-, six-, or seven-membered heteroaromatics (indoles, carbazoles, acridines, and dibenzazepines). The selectivity of these intramolecular transformations is uniquely ligand-controlled and offers efficient routes to four important classes of heterocycles from a common precursor.
- Tsvelikhovsky, Dmitry,Buchwald, Stephen L.
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supporting information; experimental part
p. 14048 - 14051
(2011/01/04)
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- Preparation and physicochemical characterization of a novel water-soluble prodrug of carbamazepine
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N-Acyl-urea derivatives of carbamazepine (CBZ) were synthesized through the reactions of iminostilbene with acyl-isocyanates to form N-glycyl-carbamazepine (N-Gly-CBZ, after a deprotection step) or N-acetyl-carbamazepine (N-acetyl-CBZ). N-Gly-CBZ was isolated as its water-soluble HCl salt and was designed to act as a prodrug and convert to CBZ and glycine in vivo by enzymatic cleavage of the acyl-urea bond. The stability pH-rate profiles for N-Gly-CBZ and N-acetyl-CBZ were determined. The stability of N-Gly-CBZ was found to range over four orders of magnitude with its greatest stability at pH 3-4 and a t 90 value of 5.9 day at pH 4 at 25°C. From the fit of the pH rate profile two pKa values were estimated to be 7.2 (terminal amine) and 10.0 (imide), which were independently verified using UV-visible spectroscopic analysis. The solubility of N-Gly-CBZ in aqueous solution was determined in the range of pH 5.5-7.5. The intrinsic solubility of the neutral form of the prodrug was found to be 4.4 mg/mL, and the solubility of the prodrug increased exponentially (log linear) as pH was decreased below its pKa1 value. N-Gly-CBZ was found to have an aqueous solubility in excess of 50 mg/mL at pH 4. The presence of N-Gly-CBZ was found to increase the aqueous solubility of CBZ, a degradation product. CBZ showed an 8.6-fold greater solubility in an aqueous solution containing 23 mg/mL of N-Gly-CBZ than in water alone. The solubilization of CBZ by N-Gly-CBZ was investigated by examining the diffusion coefficients of the predominant species in D2O and was found to be more consistent with stacking complex formation than micelle formation. The stability ofN-Gly-CBZ makes a ready-to-use parenteral formulation impractical, but a freeze-dried preparation for reconstitution appears to be feasible.
- Hemenway, Jeffrey N.,Jarho, Pekka,Henri, John T.,Nair, Sajiv K.,Vandervelde, David,Georg, Gunda I.,Stella, Valentino J.
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body text
p. 1810 - 1825
(2011/03/21)
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- Synthesis of new dibenzo[b,f]azepine derivatives
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This work is focused on synthesis and chemical characterization of new polycyclic compounds having dibenzo[b,f] azepine and 10,11-dihydrodibenzo[b,f] azepine moieties. We report the synthesis of four new compounds, obtained by reacting 5H-dibenzo[b,f]azepine-5-carbonyl chloride and 10,11-dihydro-5H- dibenzo[b,f]azepine-5-carbonyl chloride with 1-phenylpiperazine, and pyrrolidine, respectively. The newly synthesized compounds were characterized using chromatographic and spectroscopic methods (HPLC-UV-VIS 1H-NMR, 13C-NMR, mass spectrometry by ESI technique).
- Balaure, Paul Catalin,Costea, Ion,Iordache, Florin,Draghici, Constantin,Enache, Cristian
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scheme or table
p. 935 - 942
(2011/06/21)
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- Thermal Ring Contraction of Dibenz[b,f]azepin-5-yl Radicals: New Routes to Pyrrolo[3,2,1-jk]carbazoles
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(Chemical Equation Presented) Flash vacuum pyrolysis (FVP) of N-allyl- or N-benzyldibenz[b,f]azepine at temperatures from 750 to 950°C gives pyrrolo[3,2,1-jk]carbazole as the major product. The mechanism of the ring contraction involves dibenzazepin-1-yl radical formation, followed by transannular attack and formation of a 2-(indol-1-yl)phenyl radical which cyclizes. The mechanism is supported by independent generation of 2-(indol-1-yl)phenyl radicals by two different methods, and the use of 1-(2-nitrophenyl)indole as a radical generator gives an optimized synthetic route to pyrrolo[3,2,1-jk]carbazole (54% overall yield in two steps from indole). The first substituted pyrrolo[3,2,1-jk]carbazoles have been synthesized by FVP methods and also by reactions of the parent compound with electrophiles, leading to a range of 4-substituted pyrrolocarbazoles.
- Crawford, Lynne A.,McNab, Hamish,Mount, Andrew R.,Wharton, Stuart I.
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p. 6642 - 6646
(2008/12/22)
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- Organocatalytic oxidative dehydrogenation of dihydroarenes by dioxygen using 2,3-dichloro-5,6-dicyano-benzoquinone (DDQ) and NaNO2
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The oxidative dehydrogenation of dihydroarenes catalyzed by 2,3-dichloro-5,6-dicyano-benzoquinone(DDQ) and NaNO2 with dioxygen is reported. The combination of DDQ and NaNO2 showed high efficiency and high selectivity, compared with other benzoquinones and anthraquinones, e.g., >99% conversion of 9,10-dihydroanthracene with 99% selectivity for anthracene can be obtained at 120 °C under 1.3 MPa O2 for 8 h. Excellent results were achieved in the oxidative dehydrogenation of variety of dihydroarenes.
- Zhang, Wei,Ma, Hong,Zhou, Lipeng,Sun, Zhiqiang,Du, Zhongtian,Miao, Hong,Xu, Jie
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experimental part
p. 3236 - 3245
(2009/04/10)
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- Rearrangement of 1-Arylindoles to 5H-Dibenzazepines
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An unusual acid-catalyzed rearrangement of 1-arylindoles 1 to 5H-dibenzazepines 2 has been discovered.It can be used for the preparation of 2.The influence of the nature and the position of the substituents in the initial molecule 1 on the rearrangement is discussed.A possible mechanism of the reaction is suggested.A convenient method for preparation of 1-arylindoles 1c-k by means of arylation of 1-unsubstituted indoles with aryl halides by the Ullmann reaction is described.
- Tokmakov, Gennadii P.,Grandberg, Igor I.
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p. 2091 - 2098
(2007/10/02)
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- 5H-DIBENZAZEPINES, PART 5. COMPARATIVE STUDY OF 10,11-DIHYDRO-5H-DIBENZAZEPINE AND ITS ANALOGUES IN THE HYDROGEN TRANSFER DEHYDROGENATION REACTION
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Improved hydrogen transfer reaction of 10,11-dihydro-5H-dibenzazepine (1) was elaborated and generalized to 1,2-diphenylethane (10) and 9,10-dihydroanthracene (20) analogues.Kinetic constants and activation parameters were determined.Stereomutation of (Z)-stilbene (11) was achieved by supported palladium catalyst.
- Koehegyi, Imre,Galamb, Vilmos
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p. 109 - 114
(2007/10/02)
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- Chemoselective Reactions of Tellurium Tetraethoxide towards Thioamides and Amides
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Tellurium tetraethoxide reacts with primary thioamides at room temperature, forming nitriles in high yields. On the other hand, the reactions with amides are largely temperature-dependent, giving predominantly esters at 80 deg C and nitriles at a higher temperature. Similarly, tellurium tetraethoxide readily induces the C-N bond cleavage of ureas to give carbamates and amines.
- Omote, Kazushi,Aso, Yoshio,Otsubo, Tetsuo,Ogura, Fumio
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p. 1759 - 1761
(2007/10/02)
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- Site Selectivity and Regioselectivity of Nitrile Oxide Cycloadditions to N,N-Diarylaminoallenes
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N,N-Diarylaminoallenes were synthesized by isomerisation of the corresponding propargyl derivatives and submitted to reaction with 3,5-dichloro-2,4,6-trimethylbenzonitrile oxide. 5-Diarylamino-4-methylene-4,5-dihydroisoxazoles were formed with full site selectivity and regioselectivity. These cycloadducts were susceptible to nitrile oxide cycloaddition onto the exocyclic double bond as well as to acid-promoted amino-Claisen rearrangement.
- Broggini, Gianluigi,Molteni, Giorgio,Zecchi, Gaetano
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p. 1263 - 1278
(2007/10/02)
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- Electrochemical reduction of 5H-dibenz[b, f]azepine derivatives. Part 7: Cathodic dehalogenation reactions of 10-bromo-, 10,11-dibromo- and 10,11-dibromo-10,11-dihydro-5H-dibenz[b,f]azepines. Synthesis of 10-cycloalkylamino-5H-DIBENZ[B.F]AZEPINES
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The dcp and cv investigations of 10-bromo-5 H-dibenz[b, f]azepines 1 inaprotic medium [0.11 mol/l (C2H5)4NClO4/dimethyl formamide], the interpretation of the mechanism of the cathodic debromination and the application of the debromination reactions to preparative electrolysis have been extended to vicinal dibromides as 10,11-dibromo-5 H-dibenz[b,f]azepines 3 or 4 and 10,11-dibromo-10,11-dihydro-5 H-dibenz[b,f]azepines 5 or 6. The bromo compounds 4 can be converted into the appropriate 5 H-dibenz[b, f]azepines, the bromo compounds 5 and 6 on cathodic reduction undergothe formation of the 10,11-C,C double bond. The electrochemical debromination of 3 or 4 gives the reactive intermediates 10,11-dehydro-5 Hdibenz[b,f]azepines 11, which have been trapped to 10-cycloalkylamino-5 H-dibenz[b,f]azepines 12. An alternative synthetic sequence starting from 10-bromo-5-carbamoyl-5 H-dibenz-[b,f]azepine has been used for the preparation of 12.
- Jugelt,Gessner
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p. 426 - 432
(2007/10/02)
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- Fluorescence polarization immunoassay
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This disclosure relates to a method and reagents for determining ligands in biological fluids such as serum, plasma, spinal fluid, amnionic fluid and urine. In particular, this disclosure relates to a fluorescence polarization immunoassay procedure and to a novel class of tracer compounds employed as reagents in such procedures. The procedure disclosed combines the specificity of an immunoassay with the speed and convenience of fluorescence polarization techniques to provide a means for determining the amount of the specific ligand present in a sample.
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- Photochemistry of Acylazides. I. Photo- and Thermochemistry of 5-Azidocarbonyldibenzazepine and its Dimer
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The reactions of the title compounds, two new carbamoylazides, by photoexcitation and in the ground state, respectively, were investigated.The photochemistry of compounds 1 and 2 differs from that of other heterocycles of the same type and is determined by the azido group.They exhibit the three known kinds of reactions of carbamoylazides via singlet and triplet nitrene, respectively, and the Curtius-rearrangement forming an intramolecular insertion product 6, dibenzazepine 4 and the isocyanate.Products from triplet nitrenes are lacking in the photoreaction of the dimeric azide 2.The decomposition of the azide 1 can be sensitized by triplet energy transfer.Surprisingly, the isocyanate is also formed by triplet sensitization.Photoexcited pyrene reacts with 1 via electron transfer yielding rearrangement and triplet products, respectively.In contrast to diphenylcarbamoylazide, the reaction pathway of the thermally excited compounds leads to nitrene products mainly.
- Abraham, W.,Dreher, K.,Buck, K.,Kreysig, D.
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p. 453 - 460
(2007/10/02)
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- Process for the preparation of 5H-Dibenzo-(b, f)-azepine
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The invention refers to a new process for the preparation of a valuable intermediate, 5H-Dibenzo-(b, f)-azepine or iminostilbene by catalytic dehydrogenation of lO,ll--Dihydro-5H-dibenzo-(b, f)-azepine or iminodibenzyl in liquid phase in one step in the presence of hydrogen acceptor. Dimethylaniline or diphenylether may be used as a solvent and as catalyst, nobel metal catalysts, such as platinum or palladium on activated carbon or metaloxide catalysts, such as Fe2O3 may be used in the dehydrogena-tion reaction. Nitrotoluenes, dimethylmaleate or tetra-chlorobenzochinone may be used as hydrogen acceptors. The yield of iminostilbene is 77-82°C of the theoretical.
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- OXIDATION OF TERTIARY AMINES AND SULFIDES BY AN IRON(III)PORPHYRIN-O2-Na2S2O4 SYSTEM AS A MODEL OF CYTOCHROME P-450
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A novel cytochrome P-450 model system using iron(III)porphyrin, O2 and Na2S2O4 was studied.With this system, several tertiary amines and sulfides were oxidized to secondary amines and sulfoxides.KEYWORDS - oxidation; tertiary amine; oxidative dealkylation; sulfide; sulfoxidation; tetraphenylporphynatoiron(III); cytochrome P-450 model reaction; reductive activation of molecular oxygen; sodium dithionite
- Santa, Tomofumi,Miyata, Naoki,Hirobe, Masaaki
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p. 1252 - 1255
(2007/10/02)
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- A New Synthesis of 5H-Dibenzazepin-5-carboxamide (Carbamazepine)
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5H-Dibenzazepin-5-carboxamide (VI) has been synthesised starting from 2,2'-diformyldiphenylamine (III).III on cyclization with hydrazine hydrate in acetic acid gives the azepine (IV) which on treatment with COCl2 followed by ammonia affords VI, identical with an authentic sample.
- Sinha, A. K.,Agarwal, P. K.,Nizamuddin, S.
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p. 237 - 238
(2007/10/02)
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- Catalytic Dehydrogenation of Iminodibenzyl to Iminostilbene on Mn2O3-SnO2
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Catalytic dehydrogenation of iminodibenzyl to iminostilbene was carried out at 550 deg C on a binary oxide system of Mn2O3-SnO2.Maximum activity was observed at an Mn2O3-SnO2 ratio of 8:2; conversion was 40percent, selectivity 82percent.Mn2O3-SnO2 catalys
- Inoue, Masami,Itoi, Yasushi,Enomoto, Saburo,Ishizuka, Naoyasu,Amemiya, Hidemitsu,Takeuchi, Tadashi
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