105184-46-1

Basic information

• Product Name: CARBAZOLE-UL-14C
• CAS NO: 105184-46-1
• Molecular Formula: C12H9N1
• Molecular Weight: 167.21
• Mol File: 105184-46-1.mol
• Article Data: 319

Chemical Properties

• Appearance: /solid
• Storage Temp.: 2-8°C
• CAS DataBase Reference: CARBAZOLE-UL-14C(CAS DataBase Reference)
• NIST Chemistry Reference: CARBAZOLE-UL-14C(105184-46-1)
• EPA Substance Registry System: CARBAZOLE-UL-14C(105184-46-1)

Safety Data

• Hazard Codes: Xi,R
• Statements: 36/37/38
• Safety Statements: 26
• RIDADR: UN 2910 7
• WGK Germany: 3
• Hazardous Substances Data: 105184-46-1(Hazardous Substances Data)

Upstream product

• 357-57-3 brucine 
• 53475-34-6 8-chloro-2,3,4,9-tetrahydro-1H-carbazole 
• 56-23-5 tetrachloromethane 
• 2788-23-0 9-nitroso-9H-carbazole 
• 60-29-7 diethyl ether 
• 66536-70-7 1-cyclohexyl-1Hbenzo[d][1,2,3]triazole 
• 552-82-9 benzhydrylidene(methyl)amine 
• 1821-36-9 N-phenyl-2-cyclohexylamine 
• 530-47-2 N,N-diphenylhydrazine hydrochloride 
• 99-65-0 meta-dinitrobenzene 
• 90-41-5 2-phenylaniline 
• 86-00-0 2-nitrobiphenyl 
• 1484-13-5 9-vinyl-9H-carbazole 
• 20565-99-5 9-[(1Z)-prop-1-enyl]-9H-carbazole 

Downstream Products

• 55119-09-0 1,3,6,8-tetrabromo-9-methyl-9H-carbazole 
• 5393-41-9 3-nitro-9-nitroso-carbazole 
• 94067-00-2 9-(piperidin-1-ylmethyl)-9H-carbazole 
• 4041-19-4 9-octylcarbazole 
• 52131-82-5 9-(oxiran-2-ylmethyl)-9H-carbazole 
• 628337-00-8 3-bromo-9-octyl-9H-carbazole 
• 24301-72-2 6-bromo-9-ethyl-9H-carbazole-3-carbaldehyde 
• 274691-30-4 4-chloro-5-phenylpyrido[3,2,1-jk]carbazol-6-one 
• 171569-13-4 2-(6-carbazol-9-ylhexyl)-1,4-hydroquinone 
• 1484-12-4 N-methylcarbazole 
• 103148-94-3 9-<(Triphenylphosphoranyliden)acetyl>carbazol 
• 103148-87-4 <2-(9-Carbazolyl)-2-oxoethyl>triphenylphosphoniumbromid 
• 86-28-2 N-ethylcarbazole 
• 1484-08-8 9-butyl-9H-carbazole 

Relevant articles and documents

Photoinduced ullmann C-N coupling: Demonstrating the viability of a radical pathway

Carbon - nitrogen (C-N) bond-forming reactions of amines with aryl halides to generate arylamines (anilines), mediated by a stoichiometric copper reagent at elevated temperature (>180°C), were first described by Ullmann in 1903. In the intervening century, this and related C-N bond-forming processes have emerged as powerful tools for organic synthesis. Here, we report that Ullmann C-N coupling can be photoinduced by using a stoichiometric or a catalytic amount of copper, which enables the reaction to proceed under unusually mild conditions (room temperature or even -40°C). An array of data are consistent with a single-electron transfer mechanism, representing the most substantial experimental support to date for the viability of this pathway for Ullmann C-N couplings.

Acid-Catalyzed Intermolecular Rearrangement of N-Chlorocarbazole

The chlorination of carbazole with sodium hypochlorite in CH2Cl2, CHCl3, or CCl4 gave N-chlorocarbazole in 63-95percent yield.It rearranged in refluxing methanol to give carbazole, 3-chlorocarbazole, 1-chlorocarbazole, 3,6-dichlorocarbazole, and 1,6-dichlorocarbazole.These chlorocarbazoles were formed in an acid-catalyzed intermolecular reaction.In the presence of potassium carbonate dechlorination of N-chlorocarbazole was observed.No evidence for an intramolecular rearrangement was found.

Dearomatization-Rearomatization Strategy for Synthesizing Carbazoles with 2,2′-Biphenols and Ammonia by Dual C(Ar)-OH Bond Cleavages

Carbazole is an essential building block in various pharmaceuticals, agrochemicals, natural products, and materials. For future sustainability, it is highly desirable to synthesize carbazole derivatives directly from renewable resources or cheap raw materials. Phenolic compounds are a class of degradation products of lignin. On the other hand, ammonia is a very cheap industrial inorganic chemical. Herein, an efficient dearomatization-rearomatization strategy has been developed to directly cross-couple 2,2′-biphenols with ammonia by dual C(Ar)-OH bond cleavages. This strategy provides a greener pathway to synthesize valuable carbazole derivatives from phenols.

Dehydrogenation of 1,2,3,4-tetrahydroquinoline and its related compounds: Comparison of Pd/C-ethylene system and activated carbon-O2 system

Dehydrogenation of substituted 1,2,3,4-tetrahydroquinoline, 1,2,3,4-tetrahydroisoquinoline, and 1,2,3,4-tetrahydrocarbazole proceeded using Pd/C-ethylene system (method A) or activated carbon-O2 system (method B) to give the corresponding heteroaromatic compounds.

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Acid-Catalyzed Hydrolysis of Acylpyrroles and Their Derivatives

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Ring contracting sulfur extrusion from oxidized phenothiazine ring systems

Lithium, used in conjunction with sodium metal, produces a high yield of carbazole when reacted with phenothiazine-5-oxide or phenothiazine-5,5-dioxide. A high yield of 9-ethylcarbazole is also produced when these reagents react with 10-ethyl-phenothiazine, 10-ethylphenothiazine-5-oxide, and 10- ethylphenothiazine-5,5-dioxide. Degassed Raney nickel produces carbazole in high yield when reacted with phenothiazine and phenothiazine-5-oxide. A moderate yield of 9-ethylcarbazole is produced when n-butyllithium is reacted with 10-ethylphenothiazine-5-oxide.

Synthesis of the Carbazole Scaffold Directly from 2-Aminobiphenyl by Means of Tandem C–H Activation and C–N Bond Formation

An efficient method for the synthesis of the carbazole scaffold was designed and investigated. The method was developed to produce substituted carbazoles by an intramolecular combination of a free amine group and an arene. The steps of the method involved tandem Pd-catalyzed C–H activation and intramolecular C–N bond formation. The method showed good functional group tolerance, and substituent(s) could be on either of the two rings or on both of the two rings of the 2-aminobiphenyl substrate. After ring closure, the reduced Pd catalyst was oxidized to PdIIby hydrogen peroxide. The novel method was also demonstrated to operate excellently with the corresponding 2-N-acetylaminobiphenyls.

Double N-arylation of primary amines: Carbazole synthesis from 2,2′-biphenyldiols

(Chemical Equation Presented) The double N-arylation of primary amines with 2,2′-biphenylylene ditriflates was investigated for the synthesis of multisubstituted carbazoles. Palladium complexes supported by 2-dicyclohexylphosphino-2′-methylbiphenyl or Xantphos [4,5- bis(diphenylphosphino)-9,9-dimethylxanthene] were found to be efficient catalysts for the reaction. The catalysts allow the use of anilines with an electron-donating or electron-withdrawing substituent and multisubstituted 2,2′-biphenylylene ditriflates as substrates. Ammonia equivalents, such as O-tert-butyl carbamate, are also employable as a nitrogen source to give the N-protected carbazoles which can easily give the corresponding N-unsubstituted carbazoles after deprotection. By using this methodology, a carbazole alkaloid, mukonine, is synthesized in 40% yield for five steps, in comparable efficiency to the recent precedents.

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Dehydrocyclization of diphenylamine to carbazole over platinum-based bimetallic catalysts

Gas phase dehydrocyclization of diphenylamine (DPA) to carbazole over monometallic and bimetallic 0.4 wt Pt-based catalysts in a fixed bed reactor was studied in the presence of hydrogen at a temperature of 550 °C. Alumina and carbon supported Pt catalysts showed very high initial activity (> 95). The selectivity for carbazole over carbon supported Pt catalysts was slightly lower. Doping of the catalyst with potassium led to an increase in the selectivity for carbazole by 15. Bimetallic Pt-Sn catalysts prepared by co-impregnation were less selective than catalysts prepared by successive impregnation. The selectivity for carbazole over bimetallic Pt-Sn catalysts prepared by successive impregnation was 75, but their activity decreased with increased Sn loading. Highly active and reasonably selective catalysts were Ir-doped bimetallic Pt-based catalysts. The conversion of diphenylamine over Pt-Ir catalysts was above 98 and the selectivity for carbazole was nearly 55, while the lifetime was much longer.

Self-Assembled Helical Arrays for the Stabilization of the Triplet State

Room-temperature phosphorescence of metal and heavy atom-free organic molecules has emerged as an area of great potential in recent years. A rational design played a critical role in controlling the molecular ordering to impart efficient intersystem crossing and stabilize the triplet state to achieve room-temperature ultralong phosphorescence. However, in most cases, the strategies to strengthen phosphorescence efficiency have resulted in a reduced lifetime, and the available nearly degenerate singlet-triplet energy levels impart a natural competition between delayed fluorescence and phosphorescence, with the former one having the advantage. Herein, an organic helical assembly supports the exhibition of an ultralong phosphorescence lifetime. In contrary to other molecules, 3,6-phenylmethanone functionalized 9-hexylcarbazole exhibits a remarkable improvement in phosphorescence lifetime (>4.1 s) and quantum yield (11 percent) owing to an efficient molecular packing in the crystal state. A right-handed helical molecular array act as a trap and exhibits triplet exciton migration to support the exceptionally longer phosphorescence lifetime.

Photocyclization of Diphenylamine Studied by Time-Resolved Thermal Lensing. Heat of Reaction, Energetics, and Reactivity of Intermediates

The time-resolved thermal lensing (TRTL) technique was employed to study the photocyclization of diphenylamine (DPA) to form intermediate 4a,4b-dihydrocarbazole (DHC) in methanol solution at room temperature.The heat of reaction, ΔH, was determined to be (2.6+/-0.2)*102 kJmol-1 (1DPA -> 1DHC): The reaction proceeds endothermically.The ring closure step proceeds on the triplet surface (3DPA* -> 3DHC*).These triplet states are found to be isoenergetic by analyzing the time evolution of the TRTL signal. 3DHC* is located at 21 kJmol-1 above 1DHC.Furthermore, two-color laser flash photolysis experiments have revealed that the photoexcitation of intermediate 1DHC leads to the recovery of parent DPA and therefore inhibits the formation of carbazole.

Photoinduced Cross-Coupling of Amines with 1,2-Diiodobenzene and Its Application in the Synthesis of Carbazoles

A facile and efficient process for the preparation of various tertiary aminobenzenes and carbazole derivatives via photoinduced cross-coupling of amines with 1,2-diiodobenzene is reported. Mechanistic investigations indicate that the transformation proceeds via nucleo-philic addition of an amine to the benzyne intermediate accompanied with a proton transfer process, followed by an oxidative cyclization of the generated diphenylamine to furnish the corresponding carbazole products.

Radical scavenging by N-aminoazaaromatics

N-Aminoazaaromatics were found to react with nitric oxide in the presence of oxygen to afford deaminated products in high yields. The reaction proceeded almost instantaneously in various solvents including water, and one to two equivalent of NO was consumed depending upon the amount of oxygen coexisted, and 1 equivalent of N2O was released in the reaction. In addition, N-aminoazoles were deaminated by potassium superoxide to give parent azoles in good yields. Two equivalents of superoxide was consumed, and about half equivalents of both nitrite and nitrate ion were released. The results demonstrated that N-aminoazoles have ability to protect the biological system against the oxidation promoted by radicals such as nitrogen oxides and superoxide. Copyright (C) 2000 Elsevier Science Ltd.

High-yielding intramolecular direct arylation reactions with aryl chlorides

(Chemical Equation Presented) An N-heterocyclic carbene palladium catalyst system is used to promote direct arylation of a broad range of aryl chlorides to form six- and five-membered ring biaryls. An influence of the halide on the palladium precatalyst on catalyst activation has been revealed, as has a beneficial effect of NHC salts that allows the turnover numbers to be increased by simple addition of imidazolium salts to the reaction mixture.

Intramolecular Pd(II)-catalyzed oxidative biaryl synthesis under air: Reaction development and scope

(Figure Presented) New reaction conditions for intramolecular palladium(II)-catalyzed oxidative carbon-carbon bond formation under air are described. The use of pivalic acid as the reaction solvent, instead of acetic acid, results in greater reproducibility, higher yields, and broader scope. This includes the use of electron-rich diarylamines as illustrated in the synthesis of three naturally occurring carbazole products: Murrayafoline A, Mukonine, and Clausenine. A variety of side products have also been isolated, casting light on competing reaction pathways and revealing new reactivity with palladium(II) catalysis.

Synthesis of oxygenated carbazoles by palladium-mediated oxidative double C-H activation of diarylamines assisted by microwave irradiation

Microwave irradiation in the presence of palladium acetate and traces of dimethylformamide allows the fast and efficient cyclodehydrogenation of diphenylamines into carbazoles. The scope of the microwave-assisted reaction is broader than that of the one using conventional conditions in that it allows the preparation of oxygenated carbazoles without apparent loss in yield. The applicability of the method to the preparation of carbazole alkaloids has been demonstrated by the development of a total synthesis of murrayafoline A, which proceeds in 50% overall yield from commercially available materials and is the shortest and most efficient route for the preparation of this alkaloid to date. Georg Thieme Verlag Stuttgart.

Chemical Consequences of Arylnitrenes in the Crystalline Environment

UV photolysis of powdered crystals of several aryl azides at cryogenic temperatures afforded azo compounds predominantly. In the cases of p-(N-methylacetamido)phenyl azide and 2-azidobiphenyl, a CH insertion product or a carbazole was formed, competing with azo formation. These products can be considered to be formed through topotactic processes when the crystal structures are taken into account. The arylnitrenes generated in the azide crystals were monitored by ESR spectroscopy; they turned out to have extremely long half life-times, compared with those in the gas phase or in solution. Such high kinetic stabilities are ascribed to the inert environment around the generated nitrenes. The decay process of arylnitrenes in the initial stage obeyed a pseudo-first order kinetics; activation parameters were evaluated by Arrhenius plots. The activation enthalpies and entropies indicate that the diffusional processes of arylnitrenes may be the vital factors determining the kinetic stability and the product distribution in the crystalline environment.

Achieving Purely-Organic Room-Temperature Aqueous Phosphorescence via a Two-Component Macromolecular Self-Assembly Strategy

Manipulation of supramolecular behaviors and aggregation states represents an important topic in devising intriguing photofunctional systems. Here we report a two-component macromolecular self-assembly strategy for achieving aqueous room-temperature phosphorescence (RTP) in purely organic systems. Amphiphilic triblock copolymers are used to modulate the self-assembly of planar RTP molecules in aqueous solution, leading to the formation of sheet-like RTP objects with well-defined morphology, uniform crystalline nanostructures and excellent aqueous dispersity. In contrast, the addition of the planar RTP molecules into aqueous medium only leads to precipitation and quenching of RTP properties. Powder X-ray diffraction and single-crystal X-ray diffraction studies reveal that the amphiphilic triblock copolymers can assist supramolecular columnar packing of the planar RTP molecules where multiple non-covalent interactions stabilize the triplet excited states. Interestingly, it is found that luminescent signals of the sheet-like RTP objects can be extracted from strong fluorescent environments by phosphorescence mode and emission lifetime measurement.

Synthesis of Carbazoles and Related Heterocycles from Sulfilimines by Intramolecular C?H Aminations

While direct nitrene insertions into C?H bonds have become an important tool for building C?N bonds in modern organic chemistry, the generation of nitrene intermediates always requires transition metals, high temperatures, ultraviolet or laser light. We report a mild synthesis of carbazoles and related building blocks through a visible light-induced intramolecular C?H amination reaction. A striking advantage of this new method is the use of more reactive aryl sulfilimines instead of the corresponding hazardous azides. Different catalysts and divergent light sources were tested. The reaction scope is broad and the product yield is generally high. An efficient gram-scale synthesis of Clausine C demonstrates the applicability and scalability of this new method.

4,4′-Bipyridyl-Catalyzed Reduction of Nitroarenes by Bis(neopentylglycolato)diboron

4,4′-Bipyridyl worked as an organocatalyst for the reduction of nitroarenes by bis(neopentylglycolato)diboron (B2nep2), followed by hydrolysis to give the corresponding anilines. This reduction proceeded under aerobic conditions without any prepurification of substrates and reagents. We found broad functional group tolerance and compatibility for O- A nd N-protecting groups under the reaction conditions. The key in this catalytic system was the addition of B2nep2 to 4,4′-bipyridyl to form N,N′-bis[(neopentylglycolato)boryl]-4,4′-bipyridinylidene as a deoxygenating reagent of nitroarenes.

TRIFLUOROACETYLATION OF 9-METHYLCARBAZOLE. 2. PECULIARITIES OF THE REACTION DUE TO THE PRESENCE OF TRIFLUOROACETIC ACID

A satisfactory model of the intermediate in the formation of polyaryltrifluoromethylmethanes in the trifluoroacetylation of 9- methylcarbazole is 1,1,1-trifluoro-2,2-bis(9-methyl-3-carbazolyl)-2-hydroxyethane.The kinetic isotope effect of the reaction was evaluated.It is shown that the rate of the reaction is determined by the formation of a ? complex.The trifluoromethylation of 9-methyl-carbazole at 110 deg C is accompanied by demethylation of the substrate under the influence of trifluoroacetic acid.

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Metal-Free Hydroxymethylation of Indole Derivatives with Formic Acid as an Alternative Way to Indirect Utilization of CO2

The selective N-alkylation of indole substrates remains an ongoing research challenge for the relative attenuated nucleophilicity toward nitrogen. Herein, we developed the hydroxymethylation of indole derivatives to afford N-alkylated indole products with

Electrochemical Palladium-Catalyzed Intramolecular C—H Amination of 2-Amidobiaryls for Synthesis of Carbazoles

The synthesis of carbazoles based on the electrochemical Pd-catalyzed intramolecular C—H amination of 2-amidobiaryls through oxidative cross coupling has been achieved under mild reaction conditions. The reaction can be carried out in undivided cell without the addition of external chemical oxidant. Besides good functional group compatibility, the desired carbazoles can be scaled up and modified easily. Compared with previous methods, this protocol affords a simple and sustainable avenue for the construction of carbazoles.

Visible-light-driven Cadogan reaction

Visible-light-driven photochemical Cadogan-type cyclization has been discovered. The organic D-A type photosensitizer 4CzIPN found to be an efficient mediator to transfer energy from photons to the transient intermediate that breaks the barriers of deoxygenation in Cadogan reaction and enables a mild metal-free access to carbazoles and related heterocycles. DFT calculation results indicate mildly endergonic formation of the intermediate complex of nitrobiarenes and PPh3, which corresponds with experimental findings regarding reaction temperature. The robust synthetic capacity of the photoredox Cadogan reaction systems has been demonstrated by the viable productivity of a broad range of carbazoles and related N-heterocycles with good tolerance of various functionalities.