207278-66-8Relevant articles and documents
Br?nsted Base-Catalyzed Umpolung Intramolecular Cyclization of Alkynyl Imines
Kondoh, Azusa,Terada, Masahiro
, p. 3998 - 4001 (2018/03/23)
A novel “umpolung” intramolecular cyclization of alkynyl imines, in which the electrophilic imine sp2-carbon formally serves as a nucleophilic site, was developed under Br?nsted base catalysis. The reaction involves the unprecedented catalytic generation of α-aminoester enolates from α-iminoesters via the 1,2-addition of the anion of a secondary phosphite to an imine moiety followed by the [1,2]-rearrangement of a dialkoxyphosphoryl moiety from carbon to nitrogen, which is a formal umpolung process, and the intramolecular addition to an alkyne. This is a rare example of a [1,2]-rearrangement of a dialkoxyphosphoryl moiety from carbon to nitrogen to generate an α-amino carbanion and the first catalytic carbon–carbon bond forming reaction utilizing the resulting carbanion as a nucleophile.
Lewis acid-catalyzed or base-promoted regioselective cycloisomerization of N-imidoyl-o-alkynylanilines for synthesis of N-imidoyl-(1-H)-indoles and 4-alkylidene-3,4-dihydroquinazolines
Otani, Takashi,Jiang, Xue,Cho, Kinryo,Araki, Rino,Kutsumura, Noriki,Saito, Takao
supporting information, p. 1483 - 1492 (2015/05/19)
Product selectivity control for the synthesis of imidoylindoles and 4-alkylidenedihydroquinazolines from N-imidoyl-o-alkynylanilines via silver triflate-catalyzed cycloisomerization or tetrabutylammonium fluoride-promoted cyclization is described. The pro
Triflic acid-promoted cycloisomerization of 2-alkynylphenyl isothiocyanates and isocyanates: A novel synthetic method for a variety of indole derivatives
Saito, Takao,Sonoki, Yoshihiko,Otani, Takashi,Kutsumura, Noriki
supporting information, p. 8398 - 8407 (2014/12/10)
A new approach towards the synthesis of indole derivatives via triflic acid-promoted cycloisomerization with rearrangement of 2-(alkyn-1-yl)phenyl isothiocyanates and 2-(alkyn-1-yl)phenyl isocyanates has been achieved. By this methodology, structurally di
Tandem synthesis of benzo[b]carbazoles and their photoluminescent properties
Xing, Yanpeng,Hu, Binbin,Yao, Qijun,Lu, Ping,Wang, Yanguang
supporting information, p. 12788 - 12793 (2013/10/01)
5 H-Benzo[b]carbazoles were prepared through a tandem reaction between 2-ethynyl-N-triphenylphosphoranylidene anilines and α-diazoketones through ketenimine intermediates in moderate-to-good yields. By using this approach, benzo[b]benzo[5,6]indolo[3,2-h]carbazoles, fluoreno[9,1-ab]carbazoles, and fluoreno[9,1-ab]fluoreno[1′,9′:5,6,7]indolo[3,2-h]carbazoles were constructed in one pot. Moreover, the resulting products emitted light within the range 410-521a nm, with quantum yields of up to 62 %. Lord of the rings: A series of benzo[b]carbazoles was synthesized through a tandem Wolff-rearrangement/aza-Wittig-reaction/biradical-ketenimine-cyclization/1, 5-H-shift process. The products emitted intense light with high emission quantum yields (see scheme). Copyright
Efficient regioselective synthesis of indole N-carboximidamides and N-carboximidoates by a sequential aza-wittig/Ag(I)-catalyzed cyclization
Huang, Nian-Yu,Liu, Ming-Guo,Ding, Ming-Wu
supporting information; experimental part, p. 6874 - 6877 (2009/12/07)
(Chemical Equation Presented) An efficient Ag(I)-catalyzed regioselective cyclization of (2-alkynylphenyl)guanidine or (2-alkynylphenyl)isourea to indole N-carboximidamides or N-carboximidoates has been developed. The approach has the advantages of high regioselectivity, mild reaction conditions, easily accessible starting materials, and good yields. 2009 American Chemical Society.
A novel heterocumulenic Pauson-Khand reaction of alkynylcarbodiimides: A facile and efficient synthesis of heterocyclic ring-fused pyrrolinones
Saito, Takao,Shiotani, Masahiro,Otani, Takashi,Hasaba, Satoshi
, p. 1045 - 1048 (2007/10/03)
The first examples of the heterocumulenic Pauson-Khand reaction are described. Alkynylcarbodiimides undergo an intramolecular Pauson-Khand cycloaddition upon heating in the presence of Mo(CO)6 and DMSO to afford 4,5-dihydro-1H-pyrrolo[2,3-b]pyrrolin-2-ones and 1H-pyrrolo[2,3-b]indol-2-ones.
