57102-93-9Relevant academic research and scientific papers
Visible-light-promoted intramolecular C-H amination in aqueous solution: Synthesis of carbazoles
Yang, Lizheng,Zhang, Yipin,Zou, Xiaodong,Lu, Hongjian,Li, Guigen
, p. 1362 - 1366 (2018/03/26)
An effective and operationally simple protocol is reported for the synthesis of versatile carbazoles. With water as a co-solvent, visible-light rather than various metals is used to facilitate the conversion of readily available 2-azidobiphenyls under mild conditions. Various functionalized bioactive natural alkaloids, such as glycoborine, clausine C, clausine L, clausine H and clauszoline K, were synthesized efficiently with nitrogen as a sole byproduct. The reaction could be performed in water, acidic or alkaline buffer solutions, showing its potential for applications in biochemistry.
"transition-metal-free" synthesis of carbazoles by photostimulated reactions of 2′-halo[1,1′-biphenyl]-2-amines
Guerra, Walter D.,Rossi, Roberto A.,Pierini, Adriana B.,Barolo, Silvia M.
, p. 928 - 941 (2015/01/30)
An efficient and simple protocol for the preparation of a series of 9H-carbazoles by photostimulated SRN1 substitution reactions is presented. Substituted 9H-carbazoles were synthesized in low to excellent yields (up to 96%) through an intramolecular C-N bond formation of 2′-halo[1,1′-biphenyl]-2-amines by the photoinitiated SRN1 mechanism under mild and "transition-metal-free" conditions. The biphenylamines used as substrates were obtained with isolated yields ranging from 21% to 84% by two approaches: (A) the cross-coupling Suzuki-Miyaura reaction and (B) the radical arylation of anilines. Some key aspects of the proposed mechanism were evaluated at the B3LYP/6-311+G? level.
9-Azidoacridine and 9-acridinylnitrene
Taherpour, Avat Arman,Kvaskoff, David,Bernhardt, Paul V.,Wentrup, Curt
experimental part, p. 382 - 389 (2011/08/03)
Matrix photolysis as well as flash vacuum thermolysis (FVT) of 9-azidoacridine affords 9-acridinylnitrene, which is characterized by its IR and ESR spectra and is photochemically inert. FVT above 600 -C yields a mixture of the five isomeric cyanocarbazoles. Microwave-assisted reaction with diethyl- and dipropylamines in solution affords acridinylformamidine and acridinylpropionamidine, respectively. Microwave-assisted reaction with dimethylamine causes nucleophilic displacement of the azido group. Microwave-assisted 1, 3-dipolar cycloaddition with phenylacetylene yields the two regioisomeric 9-(4- and 5-phenyl-1, 2, 3-triazol-1-yl)acridines, whose structures were established by Xray crystallography.
One-electron photooxidation of N-ethylcarbazole in the presence of carbon tetrachloride. Products and mechanism of the photochemical reaction
Zelent, Bogumil,Durocher, Gilles
, p. 1654 - 1665 (2007/10/02)
The mechanism of the photodecomposition of N-ethylcarbazole (NEC) in the presence of carbon tetrachloride has been discussed on the basis of the photoproducts identified.The photodissociation of the N-ethyl bond and the electron transfer in the transiently formed ex-CT complex, 1(NEC?+...CCl4?-)*, have been proposed as the primary photochemical processes involved in the singlet excited NEC molecule.The latter, treated as the main process, leads to the radical cation of NEC, chloride ion, and trichloromethyl radical in the solvent cage, +.Cl-.CCl3>.The other reactions in the system studied are analysed following the decomposition of NEC+. in the presence of Cl- and .CCl3, which can occur by the N-ethyl group and (or) by the aromatic ring.The formation of intermediate products such as αr, αk, and γ'i(i=1,2,3, or 4) in the solvent cage gives rise to secondary photochemical reactions in the system studied.The polarity and chemical activity of the reaction media used strongly influence the nature of the secondary photochemical transformations both in and outside the solvent cage.The formation mechanism of the photochemical reaction products in CCl4 when ammonia was used, after and during irradiation, has been explained mainly by the transformations of the radical αr and cation αk as well as by the carbazyl radical β, which is also formed in the reaction medium.On the other hand, reaction of the cation γ'i explains the formation of the photoproducts in the irradiated solution of NEC with CCl4 in ethanol.These photochemical results have been compared to the photochemical reactions involved in the carbazole-CCl4 system.
