N-heterocyclic carbenes with three and six fluorous ponytails and their highly fluorophilic Rh and Ir complexes

0569339 - ÚCHP 2024 RIV CH eng J - Journal Article
Dušková, T. - Prajapati, D.S. - Kaule, P. - Červenková Šťastná, Lucie - Strašák, Tomáš - Čermák, Jan
N-heterocyclic carbenes with three and six fluorous ponytails and their highly fluorophilic Rh and Ir complexes.
Journal of Organometallic Chemistry. Roč. 986, FEB 15 (2023), č. článku 122605. ISSN 0022-328X. E-ISSN 1872-8561
Institutional support: RVO:67985858
Keywords : N-heterocyclic carbene * fluorous chemistry * rhodium complexes * iridium complexes
OECD category: Organic chemistry
Impact factor: 2.3, year: 2022
Method of publishing: Open access with time embargo

Reactions of 1-methylimidazole and 1-(1-methylethyl)imidazole with (3-iodopropyl)tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane gave the corresponding 1-alkyl-3-(3-(tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) silyl) propyl) imidazolium iodides 1 and 2. Reaction of imidazole in excess with (3-iodopropyl)tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane afforded 1-(3-(tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) silyl) propyl) imidazole 3 which was further reacted with (3-iodopropyl)tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silane to produce the doubly tagged 1,3-bis[3-(tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl) silyl) propyl] imidazolium iodide 4 and by anion exchange a tetrafluoroborate salt 5. The prepared imidazolium iodides 1,2, and 4 were then used as pre-cursors in synthesis of chlorido(cycloocta-1,5-diene)rhodium or-iridium complexes bearing Nheterocyclic carbenes with one 3-[tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)silyl]propyl-substituent and methyl-, 1-methylethyl-and another 3-[ tris(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl )silyl]propyl-substituent on nitrogens, 6 11. The metal complexes were equimolar mixtures of conformational enantiomers as was best documented by the 1H NMR signals of diastereotopic CH2 protons next to nitrogen. Fluorophilicity fi as the natural logarithm of partition coefficient Pi between fluorous and organic phase of the complexes was determined in the standard solvent system (perfluoro)methylcyclohexane/toluene. All the complexes are fluorophilic with variation of fi between 0.96 and 4.06, the complexes with high values may be classified as highly fluorophilic (heavy fluorous).(c) 2022 Elsevier B.V. All rights reserved.
Permanent Link: https://hdl.handle.net/11104/0340756