A density functional theory study on the mechanism of simultaneous trifluoromethylation and oximation of aryl-substituted ethylenes. Issue 3 (June 2022)

• Record Type: Journal Article
• Authors: Wang, Sen; Song, Wenlu; Lan, Xiaowei; Meng, Xuan; Li, Nan; Wei, Xianfu; Jing, Wenjie; Lu, Kui; Dai, Yujie
• Is Part Of: Journal of chemical research. Volume 46:Issue 3(2022)
• Publication Date: 2022-06
• Subjects: density functional theory -- difunctionalization -- free radical reaction -- oximation -- trifluoromethylation; Chemistry -- Research -- Periodicals; Chemistry -- Periodicals; 540.5
• DOI: 10.1177/17475198221104006
• Languages: English
• ISSNs: 1747-5198

Abstract

The effects of different substituents, located at the para position of the aromatic ring and at the β-carbon atom of styrenes, on difunctionalizations involving trifluoromethylation and oxime formation are investigated, showing that the difunctionalization reaction has a good adaptability to such reactants containing a range of substituents. This is important in the actual production process. It was found that proton transfer in the final tautomerism step involving transformation of a nitroso intermediate into an oxime is the rate-limiting step. The solvent effect did not influence the rate-limiting step significantly. Compared with direct proton transfer in a vacuum, the energy barrier of the final tautomerism step decreased from 57.80 kcal mol −1 in vacuum to 12.98 kcal mol −1 in water occurring via mediated proton transfer, which declines by 77.5%. When water participates in the rate-limiting steps in organic solvents, the energy barrier also decreases significantly, which indicates that a small amount of water in the organic solvent is conducive to the reaction.