Visible-Light-Driven Epoxyacylation and Hydroacylation of Olefins Using Methylene Blue/Persulfate System in Water
作者:Gabriela F. P. de Souza、Juliano A. Bonacin、Airton G. Salles
DOI:10.1021/acs.joc.8b01026
日期:2018.8.3
olefins in water using methylene blue as photoredox catalyst and persulfate as oxidant is reported. In this unprecedented unified approach, two different transformations are accomplished using only one set of reagents. The method has a broad scope spanning a range of aromatic and aliphatic aldehydes as well as conjugated and nonconjugated olefins to deliver ketones and epoxyketones from abundant and
photoepoxidation of α,β-unsaturated ketones driven by visible light in the presence of tetramethylguanidine (3b), tetraphenylporphine (H2TPP), and molecular oxygen under mild conditions was revealed. The corresponding α,β-epoxy ketones were obtained in yields of up to 94% in 96 h. The reaction time was shortened to 4.6 h by flow synthesis. The mechanism related to singlet oxygen was supported by experiments
A highly efficient catalytic kinetic resolution of 2,3-epoxy 3-aryl ketones via asymmetric ring-opening with pyrazole derivatives has been achieved by using a chiral N,N′-dioxide–Sc(iii) complex as the catalyst.
Selectfluor-Mediated Simultaneous Cleavage of C–O and C–C Bonds in α,β-Epoxy Ketones Under Transition-Metal-Free Conditions: A Route to 1,2-Diketones
作者:Heng Wang、Shaobo Ren、Jian Zhang、Wei Zhang、Yunkui Liu
DOI:10.1021/acs.joc.5b00857
日期:2015.7.2
Selectfluor-mediated simultaneous cleavage of C–O and C–C bonds in α,β-epoxyketones has been successfully achieved under transition-metal-free conditions. The reaction gives 1,2-diketone compounds in moderate to good yields involving a ring-opening/benzoyl rearrangement/C–C bond cleavage sequence under oxidative conditions.