Intramolecular Anodic Olefin Coupling Reactions and the Synthesis of Cyclic Amines
作者:Hai-Chao Xu、Kevin D. Moeller
DOI:10.1021/ja910586v
日期:2010.3.3
Anodic olefin couplingreactions using a tosylamine trapping group have been studied. The cyclizations are favored by the use of a less-polar radical cation and more basic reaction conditions. The most significant factor for obtaining good yields of cyclic product is the use of the more basic reaction conditions. However, a number of factors including the nature of both the solvent and the electrolyte
Aliphatic macrolides are used by various organisms as semiochemicals or pheromones, e. g. by the endemic Madagascanfrog family Mantellinae. Volatile, methyl-branched aliphatic macrolides occur in various species, but their identification by MS is difficult, while isolation is not possible due to the low amounts produced. Therefore, we synthesized a library of methyl-branched 11-dodecanolides to identify
Selective long-distance isomerization of terminal alkenes to silyl enol ethers proceeded via nondissociative chain walking using phenanthroline palladium catalysts. Notable features achieved taking advantage of the nondissociative chain walking mechanism include high efficiency obtained regardless of the chain length, high chemoselectivity toward terminal alkenes over internal ones, and retention of
Using the Pummerer Cyclization−Deprotonation−Cycloaddition Cascade of Imidosulfoxides for Alkaloid Synthesis
作者:Albert Padwa、Todd M. Heidelbaugh、Jeffrey T. Kuethe
DOI:10.1021/jo9915729
日期:2000.4.1
opening and formation of a 5-acetoxy-substituted 2(1H)-pyridone. This six-ring heterocyclic system constitutes a valuable building block for the synthesis of a variety of pyridine, quinolizidine, and clavine alkaloids. The cyclization-deprotonation-cycloaddition cascade has been successfully applied to the synthesis of the naturally occurring alkaloids onychnine, dielsiquinone, (+/-)-lupinine, (+/-)-anagyrine
Vinyl Grignardreagents reacted with cyclic ethers in the presence of a nickel catalyst giving rise to 2:1 coupling products 1 regioselectively. When chlorosilanes were used instead of cyclic ethers, 2:2 component coupling products 6 were obtained. A plausible reaction pathway via 1,3-butadiene–nickel complex and (2-butene-1,4-diyl)magnesium was proposed.