Stabilization of a high-spin three-coordinate Fe(iii) imidyl complex by radical delocalization

Po Chun Yang, Kuan Po Yu, Chi Tien Hsieh, Junjie Zou, Chia Te Fang, Hsin Kuan Liu, Chih Wen Pao, Liang Deng, Mu Jeng Cheng, Chun Yi Lin

研究成果: Article同行評審

8 引文 斯高帕斯(Scopus)

摘要

High-spin, late transition metal imido complexes have attracted significant interest due to their group transfer reactivity and catalytic C-H activation of organic substrates. Reaction of a new two-coordinate iron complex, Fe{N(tBu)Dipp}2 (1, Dipp = 2,6-diisopropylphenyl), with mesitylazide (MesN3) afforded a three-coordinate Fe-imidyl complex, Fe{N(tBu)Dipp}2( 00000000 00000000 00000000 00000000 11111111 00000000 11111111 00000000 00000000 00000000 NMes) (2). X-ray crystallographic characterization of single crystals of 2 showed a long Fe-N distance of 1.761(1) Å. Combined magnetic and spectroscopic (Mössbauer and X-ray absorption near edge structure spectroscopy, XANES) characterization of 2 suggests that it has an S = 2 ground state comprising an S = 5/2 Fe(iii) center antiferromagnetically coupled to an S = 1/2 imidyl ligand. Reaction of 1 and 1-azidoadamantane (AdN3) generated a putative, transient Fe{N(tBu)Dipp}2( NAd) (3′) complex that yielded an intramolecular C-H amination product, Fe{N(tBu)Dipp}{κ2-N,N′-̲N(CMe2CHNHAd)Dipp} (3). Quantum mechanical calculations further confirmed the spectroscopic assignment of 2 and 3′, as well as the differences in their stability and reactivity. Importantly, imidyl radical delocalization onto the mesityl ring significantly increased the stability of 2 and reduced its reactivity toward potential hydrogen atom transfer (HAT) reagents. In contrast, quantum mechanical calculations of 3′ revealed that the radical was solely localized on the imidyl N, leading to a high reactivity toward the proximal C-H bond of the N(tBu)Dipp ligand.

原文English
頁(從 - 到)9637-9643
頁數7
期刊Chemical Science
13
發行號33
DOIs
出版狀態Published - 2022 7月 21

All Science Journal Classification (ASJC) codes

  • 一般化學

指紋

深入研究「Stabilization of a high-spin three-coordinate Fe(iii) imidyl complex by radical delocalization」主題。共同形成了獨特的指紋。

引用此