An efficient electrochemical Minisci reaction to access 3-hydroxyalkylquinoxalin-2(1H)-ones involved hydrogen atom transfer (HAT) driven α-C(sp3)−H functionalization of alcohols was achieved. Transition metal- and chemical oxidant-free conditions were the attractive synthetic...

An efficient dehydrogenative sulfonylation of tertiary amines with thiosulfonates enabled by visible-light irradiation is developed. This protocol allows for the construction of a variety of cyclic and acyclic β-sulfonyl enamines...

Both quinoxalin-2(1H)-ones and nitriles are valuable organic compounds, and it is an interesting task to introduce cyano into quinoxalin-2(1H)-ones. Herein a regioselective CÀ H cyanation of quinoxalin-2(1H)-ones was developed with a nucleophilic cyano source TMSCN under electrochemical oxidative conditions. This process allowed the synthesis of C3 cyanated quinoxalin-2(1H)ones in moderate to excellent yields in the absence of transition-metal catalysts and organic hydroperoxides.Quinoxalin-2(1H)-ones are present in a variety of natural products and can be widely found in pharmaceutical molecules with antimicrobial, antifungal, antithrombotic, and antitumor activities, etc. [1] Quinoxalin-2(1H)-one skeleton can also be utilized as a building block in the design of fluorescent dye and fluorogenic probe. [2] A series of active quinoxalinone derivatives bearing a C3-substituted group has been extensively studied, due to their diverse biological activities. [3] Therefore, the synthesis of C3-substituted quinoxalin-2(1H)-ones has gained much attention in recent years. One of the most efficient methods to access C3-substituted quinoxalin-2(1H)-ones is the direct transformation of quinoxalin-2(1H)-ones without prefunctionalization. [4] The past years have witnessed extensive efforts on the direct C3 arylation, [5] heteroarylation, [6] alkylation, [7] trifluoromethylation, [8a] trifluoroalkylation, [8b] difluoromethylation, [8c] acylation, [9] amination, [10] alkoxylation, [11a] fluoroalkoxylation, [11b] phosphonation [12] or sulfenylation [13] of quinoxalin-2(1H)-ones. Nevertheless, the introduction of a CN group to the C3-position of quinoxalin-2(1H)-ones is still highly desirable.Compounds containing cyano functional group, namely nitriles, are a valuable class of organic compounds due to their wide application in pharmaceuticals, agrochemicals, and materials, etc. [14] Moreover, nitriles are easily converted to other important organic compounds such as amides, carboxylic acids, esters, amines, ketones, aldehydes, etc. via the cyano transformation. [15] Therefore, the facile introduction of a cyano group to organic compounds is synthetically attractive for organic chemists. Chelation-assisted transition-metal-catalyzed CÀ H activation has been well developed for the CÀ H cyanation of arenes [16] or heteroarenes [17] in the past decade (Scheme 1a). However, this strategy required the introduction of directing groups to the substrates and the utilization of expensive Rh, Ru or Pd, etc. transition-metal catalysts. [18] Direct CÀ H cyanation of arenes [19] or heteroarenes [20] is an alternative and efficient protocol because it enables the formation of cyanated products without the prefunctionalization of substrates. In these reactions, the choice of cyano sources was significant for obtaining high efficiency. Electrophilic cyanating reagents, such as BrCN, [19a] N-cyano-N-phenyl-p-toluenesulfonamide (NCTS), [19e,20b] could smoothly react with electron-rich arenes. However, these reagents had some di...

A convenient strategy is presented for the synthesis of C3‐alkylated imidazopyridines through one pot condensation and alkylation of α‐bromocarbonyl compounds with 2‐aminopyridines. A series of C3‐alkylated imidazopyridines were obtained in moderate to high yields. This strategy was also elaborated to enable the synthesis of zolpidem in short steps, which otherwise require multistep synthesis.