Aerobic, Metal-Free, and Catalytic Dehydrogenative Coupling of Heterocycles: En Route to Hedgehog Signaling Pathway Inhibitors
摘要:
The nitrosonium ion-catalyzed dehydrogenative coupling of heteroarenes under mild reaction conditions is reported. The developed method utilizes ambient molecular oxygen as a terminal oxidant, and only water is produced as byproduct. Dehydrogenative coupling of heteroarenes translated into the rapid discovery of novel hedgehog signaling pathway inhibitors, emphasizing the importance of the developed methodology.
A mild and versatile method for the synthesis of some novel indole‐1‐carbinols has been developed via one‐pot reaction of indoles and paraformaldehyde in the presence of an excess of CaO, MgO, ZnO or TiO2. The solvent‐free reaction provided all the indole derivatives in moderate to good yields and short reaction times. Moreover, the effect of some selected indole‐1‐carbinols on cell proliferation of
Generation of a Key Synthon of Indole Alkaloid Synthesis by Palladium(II)‐Catalyzed Indole 2‐Methylenephosphorylation
作者:Yuan Niu、Peng‐Bo Bai、Qin‐Xin Lou、Shang‐Dong Yang
DOI:10.1002/cctc.202000415
日期:2020.7.21
A palladium‐catalyzed Catellani‐type reaction of indole with diethyl (iodomethyl)phosphonate has been developed. This new protocol provides an efficient and concise route to 2‐methylene phosphonate indoles, which are key synthons for the construction of indolealkaloids.
作者:Oscar Lozano、George Blessley、Teresa Martinez del Campo、Amber L. Thompson、Guy T. Giuffredi、Michela Bettati、Matthew Walker、Richard Borman、Véronique Gouverneur
DOI:10.1002/anie.201103151
日期:2011.8.22
Enantioenriched fluorinated heterocycles can be prepared through fluorocyclizations of prochiral indoles (see scheme; Ts=tosyl, Bn=benzyl, Boc=tert‐butoxycarbonyl). More than twenty examples for this cascade fluorination–cyclization, which is catalyzed by cinchona alkaloids and employs N‐fluorobenzenesulfonimide as the electrophilic fluorine source have been explored, and an unprecedented catalytic
“On Water” Direct and Site-Selective Pd-Catalysed CH Arylation of (NH)-Indoles
作者:Lionel Joucla、Nelly Batail、Laurent Djakovitch
DOI:10.1002/adsc.201000512
日期:2010.11.22
communication describes the development of a versatile catalytic system based on palladium(II) acetate/bis(diphenylphosphino)methane [Pd(OAc)2/dppm] that works “on water” giving site-selective CH arylation of (NH)-indoles without protecting or directing groups. Remarkably, the control of regioselectivity was achieved by small changes in the “extra-catalytic” base/halide partners. These innovative methodologies
Pyridylmethylamine-Palladium Catalytic Systems: A Selective Alternative in the C−H Arylation of Indole
作者:Serge Perato、Benjamin Large、Qiao Lu、Anne Gaucher、Damien Prim
DOI:10.1002/cctc.201601275
日期:2017.2.6
A highly efficient pyridylmethylamine‐Pd alternative catalytic system for the C−H arylation of indole was explored. Variously substituted aryl groups were regio‐ and chemoselectively installed at the indole nucleus by using barium hydroxide as the base. The method was found to be efficient even in the presence of hindered coupling partners and Pd‐reactive bonds.