Diastereoselective [4 + 1] Cycloaddition of Alkenyl Propargyl Acetates with CO Catalyzed by [RhCl(CO)2]2
journal contributionposted on 20.02.2016 by Wei Chen, Jia-Hui Tay, Xiao-Qi Yu, Lin Pu
Any type of content formally published in an academic journal, usually following a peer-review process.
A class of alkenyl propargyl acetates, RCH(OAc)CCC(CH3)CH2 (5), are found to undergo [4 + 1] cycloaddition with CO (1 atm) in the presence of [RhCl(CO)2]2 in refluxing 1,2-dichloroethane to give cyclopentenones (6) in good yields. It has been demonstrated that, when the R group of 5 is a phenyl group bearing o-electron-withdrawing substituents, up to 10:1 diastereoselectivity and 96% yield can be achieved for the [4 + 1] cycloaddition. This process provides a convenient method to construct highly functionalized cyclopentenones that are useful in organic synthesis.