Persistent Radical Pairs between N‐Substituted Naphthalimide and Carbanion Exhibit pKa‐Dependent UV/Vis Absorption. Issue 56 (16th September 2020)

• Record Type: Journal Article
• Authors: Nie, Xiancheng; Su, Hao; Chen, Xiaoyu; Huang, Wenhuan; Huang, Linkun; Chen, Biao; Miao, Hui; Jiang, Jun; Wang, Tao; Zhang, Guoqing
• Is Part Of: Chemistry. Volume 26:Issue 56(2020)
• Page Start: 12743
• Page End: 12746
• Publication Date: 2020-09-16
• Subjects: carbanions -- pKa -- radical pairs -- UV/Vis absorption; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201905865
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: A new strategy was devised for estimating and screening p K a values among different carbon acids under ambient conditions by using the UV/Vis absorption spectrum of persistent radical pairs (PRPs), which are generated from an N‐substituted naphthalimide (NNI) derivative in the presence of various carbanions in organic solutions. The electron paramagnetic resonance (EPR) spectroscopy was used to examine the presence of radicals. Unexpectedly, it was discovered that the UV/Vis spectrum of PRPs reveals a distinct linear relationship between the PRP absorption and the p K a value of a corresponding carbon acid, which is likely due to the energy difference among different RPRs. The finding may offer organic chemists an alternative reference to conduct carbanion‐mediated reactions in various organic solutions. Abstract : Fast screening of p K a : The UV/Vis absorption spectrum of carbanion radical pairs can serve as a tool to screen p K a values of various carbon acids.