Mahima Gupta, Vaibhav Pramod Charpe, Kuo Chu Hwang
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引用次数: 0
Abstract
We have developed a singlet oxygen (1O2)-mediated regioselective thiocyanation of terminal alkynes, indoles, pyrrole, anilines, and phenols using ammonium thiocyanate (NH4SCN) as an SCN source under visible light irradiation at room temperature. The oxidative thiocyanation of terminal alkynes forms α-keto thiocyanates, while indoles, pyrrole, anilines, and phenols regioselectively form the respective thiocyanate products. Herein, thiocyanate (SCN anion) undergoes single electron transfer (SET) by transferring an electron to singlet oxygen and forms an •SCN radical, which readily reacts with substrates to form thiocyanate products. Green chemistry metrics and Eco-scale evaluations signify that the current oxidative and regioselective thiocyanation protocol is an acceptable green organic synthesis process. Moreover, this method requires a simple reaction setup and uses inexpensive NH4SCN as an SCN source, O2 as an oxidant, and low-energy visible light. Thus, the current oxidative thiocyanation process is mild, green, highly efficient, eco-friendly, and environmentally feasible.
期刊介绍:
ACS Sustainable Chemistry & Engineering is a prestigious weekly peer-reviewed scientific journal published by the American Chemical Society. Dedicated to advancing the principles of green chemistry and green engineering, it covers a wide array of research topics including green chemistry, green engineering, biomass, alternative energy, and life cycle assessment.
The journal welcomes submissions in various formats, including Letters, Articles, Features, and Perspectives (Reviews), that address the challenges of sustainability in the chemical enterprise and contribute to the advancement of sustainable practices. Join us in shaping the future of sustainable chemistry and engineering.