Synthesis of 4-trifluoromethylazetidin-2-ones by a novel 2+2 photocycloaddition of 3-trifluoromethyl-quinoxalin-2-one or -1,4-benzoxazin-2-one to ketene.
A direct C–H alkylation of quinoxalinones at the C‐3 position with sodiumalkylsulfinates and phenyliodine(III) dicarboxylates has been developed under catalyst‐free conditions. A series of 3‐alkylquinoxalinones were afforded in moderate to excellent yields in this protocol, which offers a practical and efficient access to biologically interesting 3‐alkylquinoxalin‐2(1H)‐one derivatives.
Visible-light induced C3-H trifluoromethylation of quinoxalin-2(1H)-ones with CF3SO2Cl under external photocatalyst-free conditions
作者:Xia Mi、Beibei Cui、Jingyu Zhang、Chao Pi、Xiuling Cui
DOI:10.1016/j.tetlet.2022.153693
日期:2022.3
light-induced C-H trifluoromethylation of quinoxalin-2(1H)-ones with CF3SO2Cl as CF3 radical source under photocatalyst-free conditions. The reaction proceeds smoothly through a radical process in the absence of photocatalyst and oxidant in moderate to good yields, thus offering an efficient and green method for the synthesis of 3-trifluoromethyl quinoxalin-2(1H)-ones.
本文报道了在无光催化剂条件下,以 CF 3 SO 2 Cl 作为 CF 3自由基源的 quinoxalin-2(1 H )-ones的可见光诱导 CH 三氟甲基化。该反应在没有光催化剂和氧化剂的情况下以中等至良好的收率通过自由基过程顺利进行,从而为合成3-三氟甲基喹喔啉-2( 1H )-酮提供了一种高效、绿色的方法。
Direct C−H Trifluoromethylation of Quinoxalin-2(1<i>H</i>
)-ones under Transition-Metal-Free Conditions
herein is a direct C−H trifluoromethylation of quinoxalin‐2(1H)‐ones with sodium trifluoromethanesulfinate. This protocol affords a series of 3‐trifluoromethylquinoxalin‐2(1H)‐one derivatives in moderate to excellent yields under transition‐metal‐freeconditions. The present methodology features utilization of the inexpensive trifluoromethyl source without transition‐metal‐catalysts, mild reaction conditions
An efficient approach using a photocatalytic strategy for C−Hperfluoroalkylation of quinoxalinonesunderaerobicoxidationcondition has been developed. Such transformation employs readily available sodium perfluoroalkanesulfinates as perfluoroalkylation reagents and demonstrates good functional group compatibility, affording corresponding products in moderate to good yields. Compared with previous