ChemInform Abstract: Synthesis of 2,9-Dialkylated Phenanthro[1,2-b:8,7-b′]dithiophenes via Cross-Coupling Reactions and Sequential Lewis Acid-Catalyzed Regioselective Cycloaromatization of Epoxide.

ChemInform ◽  
2014 ◽  
Vol 45 (51) ◽  
pp. no-no
Author(s):  
Keita Hyodo ◽  
Hikaru Nonobe ◽  
Shuhei Nishinaga ◽  
Yasushi Nishihara
Keyword(s):  
Lewis Acid ◽  
Cross Coupling ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Acid Catalyzed

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.

Lewis Acid-Promoted Suzuki Reaction using Palladium Chloride Anchored on a Polymer as a Catalyst

2008 ◽  
Vol 61 (8) ◽  
pp. 610 ◽  
Author(s):  
Guozhi Fan ◽  
Hanjun Zhang ◽  
Siqing Cheng ◽  
Zhandong Ren ◽  
Zhijun Hu ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Lewis Acid ◽  
Lewis Acids ◽  
Heterogeneous Catalysts ◽  
Suzuki Reaction ◽  
Cross Coupling ◽  
Palladium Chloride ◽  
Coupling Reactions ◽  
Cross Coupling Reactions ◽  
Recoverable Catalyst

Palladium chloride anchored on polystyrene modified by 5-amino-1,10-phenanthroline was prepared and used as an efficient recoverable catalyst for Suzuki cross-coupling reactions. The heterogeneous catalysts can be easily separated from the reaction mixture and reused for five cycles without significant Pd leaching and loss of catalytic activity. Rate enhancement in the Suzuki reaction by Lewis acids was also studied.

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.

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