K₂S₂O₈ mediated C-3 arylation of quinoxalin-2(1H)-ones under metal-, photocatalyst- and light-free conditions

Abstract

C-3 arylation protocols of quinoxalin-2(1H)-ones with arylhydrazines and aryl boronic acids under metal-, photocatalyst- and light-free conditions using non-toxic K2S2O8.

K2S2O8 Mediated Three‐component Radical Cascade C3 Alkylation of Quinoxalin‐2(1H)‐ones with Vinylarenes and 4‐Hydroxycoumarins/4‐Hydroxy‐6‐methyl‐2‐pyrone

“…However, with Na 2 S 2 O 8 and (NH 4 ) 2 S 2 O 8 , we got the product in a slightly lower yield compared to K 2 S 2 O 8 , while DTPB and TBPB failed to give the product (Table 1, entries [11][12][13][14]. The temperature variation revealed 70 °C as the optimum temperature (Table 1, entries [15][16][17]. Further, the reaction at 70 °C under oxidant-free conditions leads to the formation of product in a mere 5 % yield (Table 1, entry 18).…”

“…[6][7][8][9][10][11] Consequently, several research groups have developed many synthetic methodologies to access its C3substituted derivatives using different radical sources. [12] Numerous reports can be found concerning arylation, [7][8][9][13][14][15][16][17][18][19] aminations, [20] acylations, [10,[21][22][23][24] phosphorylation, [6,[25][26][27] thiolation, [28] etc. But functionalization of quinoxalinones using 1,3-diketones is relatively less explored.…”

Recent Advances in the Transition-Metal-Free Arylation of Hetero­arenes

“…Baishya and co-workers reported an effective method for the regioselective C-3 arylation of quinoxaline-2(1H)-ones using arylhydrazines as the aryl source and potassium persulfate (Scheme 27). 36 Moreover, arylation of quinoxaline-2(1H)-ones has been demonstrated in the presence of potassium carbonate and potassium persulfate in aqueous medium using arylboronic acids as the arylation source. Potassium persulfate enables the production of aryl radicals from aryl hydrazines and arylboronic acids and drives oxidation processes.…”

Sunlight Induced and Recyclable g-C3N4 Catalyzed C-H Sulfenylation of Quinoxalin-2(1H)-Ones

“…Quinoxalin-2(1 H )-one is a privileged structural moiety, which exhibits various biological activities and pharmacological properties [ 1 , 2 ]. Consequently, a large number of 3-substituted quinoxalinones are prepared via direct C3–H functionalization of quinoxalin-2(1 H )-ones in recent years, mainly including alkylation [ 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ], arylation [ 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 ], acylation [ 26 , 27 , 28 , 29 , 30 , 31 ], alkoxylation [ 32 , 33 , 34 , 35 ], sulfenylation [ 36 , 37 , 38 ], amination [ 39 , 40 , 41 , 42 , 43 , 44 ], phosphonation [ 45 , 46 , 47 , 48 , 49 ] and trifluoromethylation [ 50 , …”