Upon exposure to a catalytic amount of [RhCl(CO)2]2 in 1,4‐dioxane, homopropargylallene‐alkynes underwent a novel cycloisomerization accompanied by the migration of the alkyne moiety of the homopropargyl functional group to produce six/five/five tricyclic compounds in good yields. A plausible mechanism was proposed on the basis of an experiment with 13C‐labeled substrate. The resulting tricyclic derivatives
An Unusual Ruthenium-Catalyzed Cycloisomerization of Alkynes and Propargyl Alcohols
作者:Barry M. Trost、Michael T. Rudd
DOI:10.1021/ja012672a
日期:2002.4.1
CpRu(NCCH3)3+PF6- catalyzes the cycloisomerization of diyne-ols to alpha,beta,gamma,delta-unsaturated aldehydes and ketones in good-to-excellent yields. 1-Hydroxy-2,7-diynes and 1-hydroxy-2,8-diynes can be utilized to form highly functionalized five- and six-membered rings, respectively. Tertiary as well as secondary propargyl alcohols are cycloisomerized to a single isomeric product. A wide variety
Ruthenium-Catalyzed Decarbonylative Cyclization of 1,6-Diynes
作者:Carlos González-Rodríguez、Jesús A. Varela、Luis Castedo、Carlos Saá
DOI:10.1021/ja0752888
日期:2007.10.1
Ruthenium-catalyxed tandem cyclization-decarbonylation of terminal 1,6-diynes give exo -alkykidenecyclopentanes. The starting point of this process is likely to be the formation of an Ru-vinylidene complex.
Stereospecific and Stereoselective Rhodium(I)-Catalyzed Intramolecular [2+2+2] Cycloaddition of Allene-Ene-Ynes: Construction of Bicyclo[4.1.0]heptenes
Treatment of the allene‐ene‐yne substrates with [RhCl(CO)2}2] effected the intramolecular [2+2+2]‐type ring‐closing reaction to produce various of tri‐ and tetracyclic derivatives containing a cyclopropane ring. The reaction is highly stereoselective as well as stereospecific with good to excellent yields.