An enantioselective alkoxycarbonylation-amination cascade process of terminalallenes with CO, methanol, and arylamines has been developed. It proceeds under mild conditions (room temperature, ambient pressure CO) via oxidative Pd(II) catalysis using an aromatic spiroketal-based diphosphine (SKP) as a chiral ligand and a Cu(II) salt as an oxidant and affords a wide range of α-methylene-β-arylamino
Palladium-Catalyzed Oxidative Carbonylative Coupling of Arylallenes, Arylboronic Acids, and Nitroarenes
作者:Hui-Qing Geng、Jin-Bao Peng、Xiao-Feng Wu
DOI:10.1021/acs.orglett.9b02925
日期:2019.10.18
In this Letter, a palladium-catalyzed multicomponent procedure for the selective synthesis of α-substituted α,β-unsaturated ketones has been developed. With readily available allenes, arylboronicacids, and nitroarenes as the substrates, the reaction proceeds selectively to the desired α-substituted enones. Notably, no manipulation of carbon monoxide gas is needed here, and Mo(CO)6 has been applied
Copper-Catalyzed Difunctionalization of Allenes with Sulfonyl Iodides Leading to (<i>E</i>)-α-Iodomethyl Vinylsulfones
作者:Ning Lu、Zhiguo Zhang、Nana Ma、Conghui Wu、Guisheng Zhang、Qingfeng Liu、Tongxin Liu
DOI:10.1021/acs.orglett.8b01765
日期:2018.7.20
A highly regioselective iodosulfonylation of allenes in the presence of CuI and 1,10-phenanthroline has been developed for the synthesis of various useful (E)-α-iodomethyl vinylsulfones in moderate to excellent yields. This practical reaction is fast, operationally simple, and in particular, proceeds under very mild conditions to afford the target products with high regio- and stereoselectivity. The
作者:Steven A. Fleming、Sean M. Carroll、Jennifer Hirschi、Renmao Liu、J. Lee Pace、J. Ty Redd
DOI:10.1016/j.tetlet.2004.03.037
日期:2004.4
We have used asymmetricdihydroxylation (AD) of allenes in order to synthesize chiral α-hydroxy ketones. This methodology has been applied to several aryl-substituted allenes. We have found that electron donating groups on the aromatic ring increase the efficiency of the reaction.
Cobalt-Catalyzed C–H Activation and [3 + 2] Annulation with Allenes: Diastereoselective Synthesis of Indane Derivatives
作者:Arnab Dey、Chandra M. R. Volla
DOI:10.1021/acs.orglett.1c01521
日期:2021.7.2
ve [3 + 2] annulation reaction has been achieved, employing allenes as the annulation partners. The selective 2,3-migratory insertion of allenes with arylcobalt(III) species and the subsequent intramolecular diastereoselective nucleophilic addition of η1-allylcobalt onto the imine resulted in [3 + 2] annulation over the alternative [4 + 2] annulation. Furthermore, the oxidative annulation obviates