Efficient Synthesis of Dibenzo[<i>a</i>,<i>c</i>]cyclohepten-5-ones via a Sequential Suzuki−Miyaura Coupling and Aldol Condensation Reaction
作者:Young Lok Choi、Chan-Mo Yu、Bum Tae Kim、Jung-Nyoung Heo
DOI:10.1021/jo900508z
日期:2009.5.15
strategy for the synthesis of a 7-membered-ring system with a Suzuki−Miyaura coupling followed by an acid/base-promoted intramolecular aldol condensation reaction has been developed. The reaction of 2′-bromoacetophenones with 2-formylphenylboronic acids in the presence of Pd(OAc)2 and CataCXium PIntB L8 efficiently provided biaryl compounds, which were transformed to a wide array of dibenzo[a,c]cyclohepten-5-ones
Unusual redox play of Mo(V/IV) during oxidative aryl–aryl coupling
作者:Kristina Hackelöer、Siegfried R. Waldvogel
DOI:10.1016/j.tetlet.2012.01.062
日期:2012.3
The oxidative treatment of a suitable 1,3-diarylpropene precursor by MoCl5 causes a series of redox steps yielding a dimer of dibenzo[a,c]cycloheptene. After the oxidative aryl–aryl bond formation, a C,H activation occurs providing a tropylium intermediate. Upon aqueous workup the metal waste acts as reductive media generating the dimer in an almost quantitative manner. The oxidative generation of
Electrochemical Multicomponent Synthesis of Alkyl Alkenesulfonates using Styrenes, SO<sub>2</sub> and Alcohols
作者:Aloisio de A. Bartolomeu、Florian A. Breitschaft、Dieter Schollmeyer、Ronaldo A. Pilli、Siegfried R. Waldvogel
DOI:10.1002/chem.202400557
日期:2024.4.11
A first of its kind electrochemical approach for the direct synthesis of alkyl alkenesulfonates using styrenes, SO2 stock solution and alcohols was developed. The reaction features the in-situ generation of a monoalkylsulfite species with subsequent radical addition to an anodically oxidized styrene substrate. The applicability of the protocol was demonstrated with a broad scope as well as a gram-scale
Lignanes. 17. Recherches sur la synthèse totale d'un norcyclonéolignane, la métaséquirine-B
作者:Jean-Yves Sancéau、Robert Dhal、Eric Brown
DOI:10.1016/s0040-4020(01)87016-2
日期:1994.3
The total synthesis of the racemic furano bisbenzocycloheptene 3 is described. The compound 3, which contains five asymmetric centres, is the 5,8-bis-epimer of the tetra--methyl derivative of metasequirin-B (1), a norcycloneolignan of unusual structure.