Catalytic enantioselective alkenylation is an efficient method to construct chiral alkene molecules, but the asymmetric alkenylation of simple alkenes catalyzed by metal-free catalysts remains an elusive challenge. Herein, we reported an asymmetric alkenylation of benzoxazinones with diarylethylenes by utilizing a B(C6F5)3/chiral phosphoric acid catalyst. A broad of benzoxazinones and diarylethylenes with electron-withdrawing and electron-donating groups were tolerated (up to 95% yield and 97.5:2.5 e.r.) in the methodology under mild reaction conditions. Moreover, the synthetic utility was confirmed by the scaled-up reaction and transformations of the products. The mechanism was preliminarily explored by control reactions, nonlinear effect experiment and DFT calculations.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |