Renewable reagent for nucleophilic fluorination

Alič, Blaž (author), Petrovčič, Jan (author), Jelen, Jan (author), Tavčar, Gašper (author), Iskra, Jernej (author)

Herein, we report a study on the reactivity of three 1,3-diarylimidazolium-based fluoride reagents, with a general formula of [IPrH][F(HF)$_n$] (n = 0, 1, or 2), that tackle the challenges of limited solubility, hygroscopicity, instability, and laborious preparation procedures of nucleophilic fluoride reagents. Fluorination of 4-tert-butylbenzyl bromide reveals that trifluoride [IPrH][F(HF)$_2$] is the most selective reagent. Microwave-assisted activation coupled with the addition of sterically hindered amine DIPEA or alkali metal fluorides increases the rate of fluorination with [IPrH][F(HF)$_2$], making it an excellent reagent for the fluorination of various organic substrates. The scope of substrates includes benzyl bromides, iodides, chlorides, aliphatic halides, tosylates, mesylates, α-haloketones, a silyl chloride, acyl and sulfuryl chlorides, and a nitroarene. The exceptional stability of the air-stable and nonhygroscopic [IPrH][F(HF)$_2$] reagent is illustrated by its convenient synthesis and detailed experimental regeneration protocol using hydrofluoric acid without organic solvents.

• Language: English
• Keywords: fluorination, anions, polyfluorides, halogenation, reactivity, reagents, green chemistry, chemical reactions
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2022
• Number of pages: Str. 5987-5993
• Numbering: Vol. 87, iss. 9
• PID: 20.500.12556/RUL-140531
• UDC: 547:66.094.41
• ISSN on article: 0022-3263
• DOI: 10.1021/acs.joc.2c00247
• COBISS.SI-ID: 116482051
• Publication date in RUL: 15.09.2022

Record is a part of a journal

• Title: Journal of organic chemistry
• Shortened title: J. org. chem.
• Publisher: American Chemical Society
• ISSN: 0022-3263
• COBISS.SI-ID: 235287

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: fluoriranje, anioni, polifluoridi, halogeniranje, reaktivnost, reagenti, zelena kemija