Rhodium(III)-Catalyzed Controllable C−H Bond Functionalization of Benzamides and Vinylidenecyclopropanes: A Directing Group Determined Reaction Pathway
作者:Cheng Ji、Qin Xu、Min Shi
DOI:10.1002/adsc.201601308
日期:2017.3.20
A controllable rhodium(III)‐catalyzed C−H bond activation of benzamides and vinylidenecyclopropanes (VDCPs) by changing the directing group from C(O)NH–OPiv to C(O)NH–OBoc has been disclosed, affording two different major products in good yields under mild condition, respectively. The substrate scope has been investigated and a plausible reaction mechanism has been also proposed on the basis of previous
A new synthetic route was developed via the nucleophilic addition of lithium alkynylide to 1-arylsulfonyl cyclopropanol 1 to afford 1-alkynyl cyclopropanol, which then reacted with aryl iodide to construct trisubstituted cross-conjugated dienones through a palladium-catalyzed process, where the key steps included the regioselective carbopalladation of arylpalladium(II) intermediate across the triple
A convenient new method was developed to prepare two types of vinyl cyclopropane derivatives through gold-catalyzed cyclization of 1-alkynyl cyclopropyl tert-butyl carbonates 2. Different from the previous reported 5-exo-dig route, the 6-endo-dig addition is the preferred pathway to provide six-membered cyclized carbonates. Two factors, including stereoelectronic effect and steric effect might affect
Gold(I)‐Catalyzed Ring Expansion of Alkynylcyclopropyl Allyl Ethers to Construct Tetrasubstituted Methylenecyclobutanones: A Mechanistic Investigation about the Character of Catalytic Amount of Water
mechanism has been proposed on the basis of deuterium and 18O‐labeling experiments, Mass spectroscopic analysis, 1H and 13Cnuclearmagneticresonance (NMR) spectroscopic tracking and density functional theory (DFT) calculations. The further transformation of these methylenecyclobutanones into polycyclic skeleton has been realized by a practical three‐step synthetic procedure. Several other transformations