Oxidative Coupling Reactions of 1,3-Diarylpropene Derivatives to Dibenzo[a,c]cycloheptenes by PIFA
作者:Kristina Hackelöer、Gregor Schnakenburg、Siegfried R. Waldvogel
DOI:10.1002/ejoc.201100918
日期:2011.11
The oxidative cyclization reactions of a variety of α-benzyl-cinnamates can be selectively performed with hypervalent iodine as an oxidant. The dibenzo[a,c]cycloheptenes were isolated in up to 55 % yield. When an oxo substrate is applied, the yield was significantly increased. With this synthetic approach, a central intermediate for the synthesis of metasequirin-B was obtained in three steps from very
Oxidative Cyclization Reaction of 2-Aryl-Substituted Cinnamates To Form Phenanthrene Carboxylates by Using MoCl<sub>5</sub>
作者:Kathrin Wehming、Moritz Schubert、Gregor Schnakenburg、Siegfried R. Waldvogel
DOI:10.1002/chem.201403442
日期:2014.9.22
The oxidative cyclization reaction of 2‐aryl cinnamates and derivatives thereof can be easily performed with MoCl5 as the oxidant. This powerful reagent allows oxidative coupling reactions for which other reagents fail. The best results are obtained when the 2‐phenyl substituent of the cinnamate is equipped with two methoxy groups. Even iodo moieties in the bay region of phenanthrene are tolerated
Molybdenum Pentachloride Mediated Synthesis of Spirocyclic Compounds by Intramolecular Oxidative Coupling
作者:Moritz Schubert、Kathrin Wehming、Anton Kehl、Martin Nieger、Gregor Schnakenburg、Roland Fröhlich、Dieter Schollmeyer、Siegfried R. Waldvogel
DOI:10.1002/ejoc.201501384
日期:2016.1
The oxidative treatment of (m)ethyl 2-aryl cinnamates equipped with methoxy groups in position 4 of the phenyl moiety promote the formation of cyclohexadienone substructures. This dealkylative oxidative C–C coupling gives access to spirocycliccompounds and avoids the construction of the corresponding phenanthrenes. Furthermore, the transformation can be expanded to other spirocyclic systems.