Difunctionalization of Alkenes via the Visible-Light-Induced Trifluoromethylarylation/1,4-Aryl Shift/Desulfonylation Cascade Reactions

Abstract

A novel visible-light-induced trifluoromethylarylation/1,4-aryl shift/desulfonylation cascade reaction using CF3SO2Cl as CF3 source was described. The protocol provides an efficient approach for the synthesis of α-aryl-β-trifluoromethyl amides and/or CF3-containing oxindoles as well as the isoquinolinediones under benign conditions.

Photocatalytic fluoroalkylation reactions of organic compounds

“…Interestingly, when the N substituent was changed from alkyl to aryl groups, only a 1,4-aryl shift was observed rather than the radical cyclization. 83 The photocatalytic reaction operates efficiently with the protocol mentioned above, but it is not necessary the use of a base. The effect of substituents of the sulfonamide group as well as of the aryl group bounded to the N atom has been examined and the corresponding products are obtained in moderate to good yields (see Scheme 24).…”

CF3SO2X (X = Na, Cl) as reagents for trifluoromethylation, trifluoromethylsulfenyl-, -sulfinyl- and -sulfonylation and chlorination. Part 2: Use of CF3SO2Cl

“…In 2015, Yang, Xia and co-workers reported that trifluoromethylated oxindole derivatives could also be accessed from N -tosylacrylamides 5 , via a similar pathway including an additional desulfonylation step ( Scheme 6 ) [ 13 ]. Both electron-withdrawing and electron-donating groups on para -position of the aryl ring were tolerated, and provided comparable yields.…”

Design for carbon–carbon bond forming reactions under ambient conditions

“…215,217,[414][415][416][417][418] It has also been observed that introduction of a trifluoromethyl group into organic compounds usually leads to improvement of their biological and physiological characteristics attributed to developing and/or improving unique physical and chemical properties in the trifluoromethyl-substituted derivatives, such as chemical and metabolic stability and bioavailability, by the incorporated trifluoromethyl group. Recently, Woo and Kim 448 have developed a visible-light-induced photoredox-catalyzed rapid protocol for the synthesis of CF 3 -substituted cyclic ketones (217) via trifluoromethylation and 1,2-carbon migration of 1-(1-arylvinyl)cyclobutanol derivatives 215 using Ru(phen) 3 449 have reported on the development of a viable visible-light-induced method for smooth implementation of trifluoromethylarylation/1,4-aryl shift/desulfonylation cascade reaction of α,β-unsaturated imide alkenes (218) using CF 3 SO 2 Cl as CF 3 source in the presence of Ru(bpy) 3 Cl 2 as the photocatalyst at room temperature, thereby yielding trifluoromethyl isoquinolinediones (219), trifluoromethyl oxindoles (220) and α-aryl-βtrifluoromethylamides (221) under varying conditions in moderate to good yield (Scheme 83). Recently, Woo and Kim 448 have developed a visible-light-induced photoredox-catalyzed rapid protocol for the synthesis of CF 3 -substituted cyclic ketones (217) via trifluoromethylation and 1,2-carbon migration of 1-(1-arylvinyl)cyclobutanol derivatives 215 using Ru(phen) 3 449 have reported on the development of a viable visible-light-induced method for smooth implementation of trifluoromethylarylation/1,4-aryl shift/desulfonylation cascade reaction of α,β-unsaturated imide alkenes (218) using CF 3 SO 2 Cl as CF 3 source in the presence of Ru(bpy) 3 Cl 2 as the photocatalyst at room temperature, thereby yielding trifluoromethyl isoquinolinediones (219), trifluoromethyl oxindoles (220) and α-aryl-βtrifluoromethylamides (221) under varying conditions in moderate to good yield (Scheme 83).…”