Self-photocatalyzed regulable alkylation of 2H-benzothiazoles with diverse aliphatic C–H donors

Abstract

Visible light-driven self-catalyzed regulable alkylation of 2H-benzothiazoles with diverse aliphatic C–H donors via the combination of HAT and self-photoredox catalysis.

Phototriggered Self-Catalyzed Three-Component Minisci Reaction: A Route to β-C(sp3) Heteroarylated Alcohols/Ethers

“…We were pleased to find that substrates bearing chloro ( 5c ) and cyano ( 5d ) groups as well as a series of diol compounds ( 5e – 5h ) were all compatible with the reaction with their functional groups preserved, which further emphasized the potential of our system for synthetic applications. Interestingly, isopropanol and cyclohexanol led to a mixture of products ( 5i and 5i′, 5j and 5j′ ) in ratios of 4.2:1 and 8.3:1, respectively, by direct dehydrative coupling between heteroarenes and alcohols, which was consistent with our previous research …”

“…For example, Li et al detailed the self-photocatalyzed methylation of diverse N -heteroaromatics using MeOH as the methylating agent. Very recently, our group disclosed self-photocatalyzed regulable alkylation of heteroarenes with diverse aliphatic C–H donors in which the heteroarene acted as a photocatalyst to induce the generation of chlorine radical, etc . Inspired by these initial results, we envisioned whether the photosensitivity of the heteroarenes could be applied to the multicomponent Minisci reaction to construct more complex molecules.…”

Efficient and selective oxidation of furfural into high‐value chemicals by cobalt and nitrogen co‐doped carbon

“…As shown in Figure 5C, typical signals of DMPO‐•OOH are observed in the EPR spectra, and the intensity of activating O 2 is determined by the order of Co SAs‐N@C > Co NPs‐N@C ≈ N@C, hinting that the mechanism of oxidative esterification involves hydroxyl radical oxidation. It has been demonstrated that N‐species on carbon is capable of activating O 2 for aerobic oxidation, [ 4,13 ] oxygen reduction reaction, [ 37 ] and epoxidation reaction. [ 38 ] As expected, the oxidative esterification of FUR was significantly blocked by bubbling N 2 (Figure 4D) or adding butylated hydroxytoluene (BHT), a free‐radical scavenger (Figure 5D), further confirming that the oxidative esterification reaction proceeded as radical oxidation.…”

“…Finally, 3 g of the powdered mixture was annealed in a glass tube furnace under an argon atmosphere with a temperature program: from room temperature to 550°C at an elevated rate of 5°C/min, kept at 550°C for 2 h and then at 900°C for 4 h, and the flow rate of argon was set at 75 ml/min. [ 4,13 ] After cooling to room temperature, approximately 150 mg of the Co SAs‐N@C catalyst was obtained.…”

“…It has been comprehensively confirmed that Co-based, N-doped carbon material is one of the most promising catalysts for oxidative esterification reactions. [4,12,13,25] Therefore, the supported Co-based catalyst was screened for aerobic oxidation of FUR in the following experiments.…”