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.
Recent Advances in “Formal” Ruthenium-Catalyzed [2+2+2] Cycloaddition Reactions of Diynes to Alkenes
作者:Silvia García-Rubín、Jesús A. Varela、Luis Castedo、Carlos Saá
DOI:10.1002/chem.200801088
日期:2008.10.29
[2+2+2] cycloaddition of 1,6-diynes to alkenes gave bicyclic 1,3-cyclohexadienes in relatively good yields. When terminal 1,6-diynes 1 were used, two isomeric bicyclic 1,3-cyclohexadienes 4 or 6 were obtained, depending on the acyclic or cyclic nature of the alkene partner. When unsymmetrical substituted 1,6-diynes 7 were used, the reaction with acyclic alkenes took place regio- and stereoselectively
A convenient and versatile procedure for the straightforward synthesis of substituted fluorenones as valuable scaffolds is described under rhodium catalysis. The present [2 + 2 + 2] cycloadditionreaction of diynes with 3-acetoxy or-3-alkoxyindenones as surrogates of the highly reactive benzocyclopentynone 2π partner allows the preparation of various fluorenone-type derivatives in good yields and provides
Cyclization/Hydrosilylation of Functionalized 1,6-Diynes Catalyzed by Cationic Platinum Complexes Containing Bidentate Nitrogen Ligands
作者:Xiang Wang、Harinath Chakrapani、James W. Madine、Michele A. Keyerleber、Ross A. Widenhoefer
DOI:10.1021/jo015986p
日期:2002.5.1
and HSiEt(3) to form 1,1-dicarbomethoxy-3-methylene-4-(triethylsilylmethylene)cyclopentane (3) in 82% isolated yield with 26:1 Z:E selectivity. Platinum-catalyzed diyne cyclization/hydrosilylation tolerated a range of functional groups including esters, sulfones, acetals, silyl ethers, amides, and hindered ketones. Diynes that possessed propargylic substitution underwent facile cyclization/hydrosilylation
Alkynylboronates and -boramides in CoI- and RhI-Catalyzed [2+2+2] Cycloadditions: Construction of Oligoaryls through Selective Suzuki Couplings
作者:Laura Iannazzo、K. Peter C. Vollhardt、Max Malacria、Corinne Aubert、Vincent Gandon
DOI:10.1002/ejoc.201100371
日期:2011.6
borylated alkynes, followed by Suzuki cross-couplings with aryl halides. Ethynylboryl pinacolate took part in cobalt-catalyzed [2+2+2] cycloadditions of all types investigated (i.e., all-intermolecular cyclotrimerization, diyne-yne cocyclization, and all-intramolecular triyne cycloisomerization). The resulting platforms gave rise to linear and angular ter- and quateraryls after Pd-catalyzed cross-coupling