95249-59-5Relevant academic research and scientific papers
Efficient Copper-Catalysed Synthesis of Carbazoles by Double N -Arylation of Primary Amines with 2,2′-Dibromobiphenyl in the Presence of Air
Do, Ha Nam,Quan, Nguyen Minh,Van Phuc, Ban,Van Tinh, Dinh,Tien, Nguyen Quyet,Nga, Truong Thi Thanh,Nguyen, Van Tuyen,Hung, Tran Quang,Dang, Tuan Thanh,Langer, Peter
supporting information, p. 611 - 615 (2021/01/21)
An efficient Cu-catalyzed synthesis of carbazole derivatives is reported, which proceeds by double C-N coupling reactions of 2,2′-dibromobiphenyl and amines in the presence of air. The reaction is robust, proceeds in high yields, and tolerates a series of amines including neutral, electron-rich, electron-deficient aromatic amines and aliphatic amines.
Olefin-Oriented Selective Synthesis of Linear and Branched N-Alkylated Heterocycles by Hydroamination
Sushmita,Aggarwal, Trapti,Saini, Kapil Mohan,Verma, Akhilesh K.
supporting information, p. 3312 - 3316 (2020/05/18)
An effective base-induced selective approach for the synthesis of linear and branched N-alkylated heterocycles by hydroamination of olefins has been described. The designed C–N bond formation method was directed through the olefin, as with styrenes only linear N-alkylated product was obtained, and acrylates gave linear as well as branched alkylated heterocycles. This protocol provided the synthesis of exclusive N-alkylated product instead of the C-3 Michael addition product. The reaction was also compatible with phenyl vinyl sulfone, thus leading to the formation of sulfone substituted heterocycles in good yield. Further, the method was utilized for the synthesis of medicinally important analogs of CB1 Cannabinoid receptor and Dimebon analogue in short reaction sequence.
Synthesis of N-Alkyl and N-H-Carbazoles through SNAr-Based Aminations of Dibenzothiophene Dioxides
Kaga, Atsushi,Nogi, Keisuke,Yorimitsu, Hideki
supporting information, p. 14780 - 14784 (2019/11/13)
Alkyl amines have become available for the synthesis of diverse N-alkyl carbazoles through twofold SNAr aminations of dibenzothiophene dioxides by using alkali metal bases. Of particular importance is the choice of counter cations on alkali metal bases, that is, i) the use of Li base for the efficient intermolecular reaction and ii) the sequential addition of heavier alkali metal bases (Na, K, or Cs) to promote intramolecular cyclization in a one-pot manner. This protocol also enables the cascade synthesis of N-H-carbazoles by using 2-phenylethylamine by removal of the 2-phenethyl group from N-(2-phenethyl) carbazoles in a single operation.
Substrate-Controlled Regio- and Stereoselective Synthesis of (Z)- and (E)- N-Styrylated Carbazoles, Aza-carbazoles, and γ-Carbolines via Hydroamination of Alkynes
Garg, Vineeta,Kumar, Pradeep,Verma, Akhilesh K.
, p. 11686 - 11702 (2018/09/21)
We report herein the substrate-controlled regio- and stereoselective hydroamination of carbazoles, aza-carbazoles, and γ-carbolines with functionalized aromatic as well as aliphatic alkynes in a KOH/DMSO system in good yields. The electronic effect of the substrates governs the stereochemistry of the product. Electron-donating alkynes provided (Z)-stereoselective products, and electron-withdrawing alkynes provided (E)-stereoselective products. This approach also provides an easy route for the synthesis of mono- and bis-hydroaminated product. The deuterium-labeling studies were also conducted to support the mechanistic pathway.
Reductive N-Arylethylation of Aromatic Amines and N-Heterocycles with Enol Ethers
V?gerl, Katharina,Ong, Duc Nghia,Bracher, Franz
, p. 1323 - 1330 (2017/12/26)
A convenient method for N-arylethylation of aromatic amines and heterocycles under mild reductive conditions was developed using (2-methoxyvinyl)(hetero)arenes as building blocks and triethylsilane/trifluoroacetic acid as reducing agent. This protocol is compatible with numerous functional groups, and aliphatic amines are inert due to protonation.
β-aminoethyltrifluoroborates: Efficient aminoethylations via Suzuki-Miyaura cross-coupling
Molander, Gary A.,Vargas, Fabricio
, p. 203 - 206 (2007/10/03)
(Chemical Equation Presented) A set of phenethylamines has been successfully prepared via Suzuki-Miyaura cross-coupling of diverse potassium β-aminoethyltrifluoroborates with aryl halides. The potassium β-aminoethyltrifluoroborates were easily prepared vi
Carbon-Skeletal Anionic Rearrangements of Tertiary Benzylic Amines: Geometric and Electronic Requirements for Generating the Spiroazacyclopropane Intermediate
Eisch, John J.,Dua, Suresh K.,Kovacs, Csaba A.
, p. 4437 - 4444 (2007/10/02)
In order to determine the scope and mechanism for the base-promoted rearrangement of tertiary amines, a wide variety of benzylic amines were treated with n-BuLi in THF or TMEDA, n-BuLi-KO-t-Bu mixtures, or KH.The following amines were examined: benzyldimethylamine, benzylmethylphenylamine, benzyldiphenylamine, N-benzylcarbazole, N-benzyl-1,2,3,4-tetrahydrocarbazole, N-benzyl-1,1a,2,3,4,4a-cis-hexahydrocarbazole, N-(2-phenylethyl)carbazole, N-(3-phenylpropyl)carbazole, N-(2-chloroethyl)carbazole, N-benzyl-9,9-dimethyl-9,10-dihydroacridine, N-benzyl-o,o'-iminodibenzyl, 9-(diphenylamino)fluorene, 9-anilino-9-phenylfluorene, 9-(methylphenylamino)fluorene, and diphenyl(diphenylmethyl)amine.In certain cases, ethylation products were obtained from the interaction of intermediate carbanions with ethylene generated by the decomposition of THF.The results are interpreted in terms of intramolecular shifts of aryl groups from nitrogen to benzylic carbon proceeding by way of a bridging aryl transition state or intermediate.
α-Lithiation of N-Alkylcarbazoles: Preparation of N-(E)-Styrylcarbazole
Katritzky, Alan R.,Saczewski, Franciszek,Marson, Charles M.
, p. 1351 - 1355 (2007/10/02)
Alkylation of carbazole with benzene gave the key intermediate N-carbazole (2).Treatment of 2 with n-butyllithium at low temperature gave an α-lithio derivative 3, which reacted with a variety of electrophiles, affording N-carbazoles 4a-g.Removal of the activating phenylthio group in 4a-g was achieved by Raney nickel desulfurization.Three successful routes to the novel N-(E)-styrylcarbazole (10) are described. 1H NMR and 13C NMR assignments of N-alkylcarbazoles are discussed.
