Marked effect of a catalytic amount of an amine on selective epoxidation of aliphatic and aromatic olefins witht-butyl hydroperoxide and a molybdenum oxide chelate
In the presence of a catalyticamount of an appropriate amine, epoxides were selectively obtained in good yields from reaction of aliphatic and aromatic olefins witht-butyl hydroperoxide and MoO2(acac)2 in carbon tetrachloride.
A new chrial organosulfide was synthesized through an unexpected Wagner–Meerwein rearrangement. This organosulfide could catalyze the epoxidation reaction of various aromatic aldehydes smoothly with benzyl bromide to give trans-diaryl epoxides in satisfactory yields (60–84%) with excellent diastereoselectivities (trans:cis=95:5–100:0) and good to excellent enantioselectivities (86–96% ee).
Dual Oxidation of Epoxides with a High-Valent Cu(III)–CF<sub>3</sub> Compound and DMSO to Access 1,2-Diketones
作者:Dou-Dou Chen、Song-Lin Zhang
DOI:10.1021/acs.joc.3c01160
日期:2023.12.15
This study reports sequential dehydrogenation and transfer oxygenation of 1,2-diarylepoxides by high-valent phenCu(III)(CF3)3 and DMSO to produce 1,2-diketones. The Cu(III)–CF3 compound serves as a CF3 radical source to abstract the hydrogen atom of the epoxide ring. The resulting ether α-carbon radical undergoes ring-opening rearrangement to give a ketone α-carbon radical intermediate, which is oxygenated