Efficient Synthesis of γ-Alkylidenetetronic Esters by Sequential Lewis Acid Catalyzed [3 + 2] Cyclizations and Palladium-Catalyzed Cross-Coupling Reactions

2001 ◽  
Vol 66 (7) ◽  
pp. 2222-2226 ◽  
Author(s):  
Peter Langer ◽  
Tobias Eckardt ◽  
Toni Schneider ◽  
Cornelia Göbel ◽  
Regine Herbst-Irmer
Keyword(s):  
Lewis Acid ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Efficient Synthesis ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed ◽  
Acid Catalyzed

scholarly journals Palladium-catalyzed cross coupling reactions of 4-bromo-6H-1,2-oxazines

2009 ◽  
Vol 5 ◽  
Author(s):  
Reinhold Zimmer ◽  
Elmar Schmidt ◽  
Michal Andrä ◽  
Marcel-Antoine Duhs ◽  
Igor Linder ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Cross Coupling ◽  
Pyridine Derivative ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Palladium Catalyzed

A number of 4-aryl- and 4-alkynyl-substituted 6H-1,2-oxazines 8 and 9 have been prepared in good yields via cross coupling reactions of halogenated precursors 2, which in turn are easily accessible by bromination of 6H-1,2-oxazines 1. Lewis-acid promoted reaction of 1,2-oxazine 9c with 1-hexyne provided alkynyl-substituted pyridine derivative 12 thus demonstrating the potential of this approach for the synthesis of pyridines.

Efficient synthesis of 2-phenyl-3-substituted furo/thieno[2,3-b]quinoxalines via Sonogashira coupling reaction followed by iodocyclization and subsequent palladium-catalyzed cross-coupling reactions

RSC Advances ◽  
2016 ◽  
Vol 6 (87) ◽  
pp. 83901-83908 ◽  
Author(s):  
Tayebeh Besharati-Seidani ◽  
Ali Keivanloo ◽  
Babak Kaboudin ◽  
Tsutomu Yokomatsu
Keyword(s):  
Coupling Reaction ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Sonogashira Coupling ◽  
Efficient Synthesis ◽  
Cross Coupling Reactions ◽  
Sonogashira Coupling Reaction ◽  
Quinoxaline Derivatives ◽  
Palladium Catalyzed

In this paper, we report the successful synthesis of new 2-phenyl-3-substituted furo/thieno[2,3-b]quinoxaline derivatives from 2-chloro-3-methoxyquinoxaline and 2-chloro-3-(methylthio)quinoxaline by a three-step approach.

Sixfold Peripheral Halogenation of Tribenzotriquinacenes: An Alternative Access to Useful TBTQ Building Blocks

Synthesis ◽  
2017 ◽  
Vol 50 (01) ◽  
pp. 175-183 ◽  
Author(s):  
Dietmar Kuck ◽  
Jens Linke ◽  
Natalia Bader ◽  
Jörg Tellenbröker
Keyword(s):  
Microwave Irradiation ◽  
Lewis Acid ◽  
Elevated Temperatures ◽  
Cross Coupling ◽  
Building Blocks ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Electrophilic Bromination ◽  
Acid Catalyzed ◽  
Derivatives Of

Sixfold electrophilic bromination and iodination of the molecular periphery of the bridgehead-tetramethylated tribenzotriquinac­ene (TBTQ) with N-bromosuccinimide (NBS) and N-iodosuccinimide (NIS), respectively, under various conditions was studied to develop an alternative preparative approach to the classical Lewis acid catalyzed bromination. Running these reactions in trifluoroacetic acid either in pure form or with chloroform as a co-solvent at elevated temperatures, or under sonication or microwave irradiation was found to give increasingly fast and efficient conversion of TBTQ to the target hexahalogenated TBTQ derivatives in excellent yields. NIS was found to be markedly more reactive than NBS, whereas N-chlorosuccimide reacted hardly. The new method was applied to the sixfold functionalization of the 4b,8b,12b-tripropyl-12d-methyl-TBTQ analogue to give the corresponding hexabromo and hexaiodo derivatives. Some sixfold C–C cross-coupling reactions of hexahalo derivatives of TBTQ were carried out in excellent yields to enlarge the three spatially orthogonal indane wings of the TBTQ core.

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