Regiocontrolled Synthesis of Ring-Fused Thieno[2,3-c]pyrazoles through 1,3-Dipolar Cycloaddition of Nitrile Imines with Sulfur-Based Acetylenes
作者:Jay Zumbar Chandanshive、Bianca Flavia Bonini、Denis Gentili、Mariafrancesca Fochi、Luca Bernardi、Mauro Comes Franchini
DOI:10.1002/ejoc.201001048
日期:2010.11
1,3-Dipolarcycloadditions of C-carboxymethyl-N-arylnitrile imines with substituted acetylenes bearing thiol or sulfone groups were studied. The sulfur controls the regiochemistry of the reaction, and this protocol was applied to the synthesis of ring-fused thieno[2,3-c]pyrazoles.
Oxidative Addition of Pd(0) to Ar−SO<sub>2</sub>R Bonds: Heck-Type Reactions of Sulfones
作者:José Luis García Ruano、José Alemán、Cristina García Paredes
DOI:10.1021/ol060608y
日期:2006.6.1
[reaction: see text] Phenyl vinyl sulfones and sulfoxides react with Pd(OAc)(2) to form styrylsulfoxides and sulfones according to the first Mizoroki-Heck reaction reported for these thio derivatives. Only sulfones are able to react by using catalytic amounts of Pd (up to 1 mol %) in the presence of Ag(2)CO(3). 1,2-Diphenylsulfonyl ethenes, alkynylphenyl sulfones, and other sulfones, less prone to act as acceptors
based on a photocatalyzed oxidative decarboxylation of oxamic acids is described. The reaction includes in situ generation of an isocyanate from the oxamic acid, using an organic dye as a photocatalyst, a hypervalent iodine reagent as an oxidant and a light source, which trigger the free-radical decarboxylation. This protocol successfully avoids the isolation, purification and storage of carcinogenic
A synthesis of novel nine-membered dienones through a cyclic acetylenic oxy-cope rearrangement: The synthesis of dl-phoracantholide I
作者:Takeshi Ohnuma、Noriaki Hata、Nobuhide Miyachi、Takeshi Wakamatsu、Yoshio Ban
DOI:10.1016/s0040-4039(00)83981-7
日期:1986.1
Phoracantholide I, having a ten-membered lactone, was synthesized through a new synthetic method which includes a cyclic acetylenic oxy-Cope rearrangement and ring-expansion by the Baeyer-Villiger oxidation of a nine-membered ketone.