BROWSE

Related Scientist

Researcher

Mahesh Sundararajan
분자활성 촉매반응 연구단
more info

Positive shift in corrole redox potentials leveraged by modest β-CF3-substitution helps achieve efficient photocatalytic C-H bond functionalization by group 13 complexes

Cited 0 time in webofscience Cited 0 time in scopus
8 Viewed 1 Downloaded
Title
Positive shift in corrole redox potentials leveraged by modest β-CF3-substitution helps achieve efficient photocatalytic C-H bond functionalization by group 13 complexes
Author(s)
Xuan Zhan; Pinky Yadav; Yael Diskin-Posner; Natalia Fridman; Mahesh Sundararajan; Zakir Ullah; Qiu-Cheng Chen; Linda J. W. Shimon; Atif Mahammed; David G. Churchill; Mu-Hyun Baik; Zeev Gross
Publication Date
2019-08
Journal
DALTON TRANSACTIONS, v.48, no.32, pp.12279 - 12286
Publisher
ROYAL SOC CHEMISTRY
Abstract
© 2019 The Royal Society of Chemistry.Tris- A nd tetrakis-β-trifluoromethylated gallium (3CF3-Ga, 4CF3-Ga) and aluminum (3CF3-Al, 4CF3-Al) corrole systems were synthesized by a facile "one-pot" approach from the respective tri- A nd tetra-iodo starting compounds using the FSO2CF2CO2Me reagent. The isolated 5,10,15-(tris-pentafluorophenyl)corrole-based compounds set the groundwork for another important β-substituent study in inorganic photocatalysis. As seen previously,-CF3 group substitution leads to red shifts in both the absorption and emission spectra compared to their unsubstituted counterparts (X. Zhan, et al., Inorg. Chem., 2019, 58, 6184-6198). All CF3-substituted corrole complexes showed strong fluorescence; 3CF3-Al possessed the highest fluorescence quantum yield (0.71) among these compounds. The photocatalytic production of bromophenol by way of these photosensitizing complexes was studied demonstrating that tris-trifluoromethylation is an important substitution class, especially when Ga3+ is present (experimental TON value in parentheses): 3CF3-Ga (192) > 4CF3-Ga (146) > 3CF3-Al (130) > 4CF3-Al (56) > 1-Ga (43) > 1-Al (18). The catalytic performance (turn-over number, TON) for benzylbromide formation (from toluene) was found to be: 3CF3-Ga (225) > 1-Ga (138) > 3CF3-Al (130) > 4CF3-Ga (126) > 1-Al (95) > 4CF3-Al (89); in these trials, benzaldehyde was also detected as a product in which 3CF3-Ga outperforms the other compounds (TON = 109). The tetra-CF3-substituted 4CF3-Ga and 4CF3-Al species exhibit a dramatic formal positive shift of 116 mV and 126 mV per [CF3] group, respectively, compared to the unsubstituted parent species 1-Ga and 1-Al. However, the absorbance values (λabs = 400 nm) of these corrole complexes (all equally concentrated: 4.0 × 10-6 M) were 3CF3-Al (0.23) > 3CF3-Ga (0.22) > 1-Al (0.21) > 1-Ga (0.20) > 4CF3-Al (0.19) > 4CF3-Ga (0.15), which helps rationalize why 3CF3-Ga performs the best among these catalysts. These new photosensitizers were carefully characterized by 1H and 19F NMR spectroscopy to help verify the number and position (symmetry) of the CF3 groups; 3CF3-Ga and 3I-Al were structurally characterized. Distortions in the corrole macrocycle imposed by the multiple β-substitution were quantified.
URI
https://pr.ibs.re.kr/handle/8788114/6584
ISSN
1477-9226
Appears in Collections:
Center for Catalytic Hydrocarbon Functionalizations(분자활성 촉매반응 연구단) > Journal Papers (저널논문)
Files in This Item:
Positive shift.pdfDownload

qrcode

  • facebook

    twitter

  • Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.
해당 아이템을 이메일로 공유하기 원하시면 인증을 거치시기 바랍니다.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse