Syntheses of Seven-Membered Rings: Ruthenium-Catalyzed Intramolecular [5+2] Cycloadditions
作者:Barry M. Trost、Hong C. Shen、Daniel B. Horne、F. Dean Toste、Bernhard G. Steinmetz、Christopher Koradin
DOI:10.1002/chem.200401065
日期:2005.4.8
The Ru-catalyzed intramolecular [5+2] cycloaddition of cyclopropylenynes is investigated with respect to the regio- and diastereoselectivity as well as the functional group compatibility of the reaction. Evidence for the mechanism as occurring through a ruthenacyclopentene intermediate is elucidated from 1) the study of the diastereoselectivity of the cycloaddition; 2) the effect of variation of substituents
Cobalt‐Catalyzed Intramolecular Reactions between a Vinylcyclopropane and an Alkyne: Switchable [5+2] Cycloaddition and Homo‐Ene Pathways
作者:Chunlin Wu、Naohiko Yoshikai
DOI:10.1002/anie.201803162
日期:2018.5.28
Cobalt–diphosphine catalysts have been found to promote intramolecular reactions between a vinylcyclopropane and an alkyne to selectively afford either the [5+2] cycloaddition product or the homo‐enereaction product under solvent control. The former product is exclusively formed in noncoordinating 1,2‐dichloroethane, whereas the latter is dominant in coordinating solvents, such as acetonitrile and
An efficient Rh-catalyst system for the intramolecular [4+2] and [5+2] cycloaddition reactions
作者:Bin Wang、Ping Cao、Xumu Zhang
DOI:10.1016/s0040-4039(00)01432-5
日期:2000.10
A new Rh-catalyst system has been developed for the [4+2] and [5+2] cycloadditionreactions. This new system shows high reactivity at room temperature and the Rh-center bears tunable phosphine ligands. Up to 1000 turnovers have been obtained for the [4+2] cycloadditionreaction at room temperature.