137658 - Gold-catalyzed regiospecific annulation of unsymmetrically substituted.pdf (1.37 MB)
Gold-catalyzed regiospecific annulation of unsymmetrically substituted 1,5-diynes for the precise synthesis of bispentalenes
journal contribution
posted on 2023-05-20, 11:20 authored by Tavakkolifard, S, Sekine, K, Reichert, L, Ebrahimi, M, Museridz, K, Michel, E, Rominger, F, Rasool BabaahmadiRasool Babaahmadi, Alireza AriafardAlireza Ariafard, Brian YatesBrian Yates, Rudolph, M, Hashmi, ASKPrecise control of the selectivity in organic synthesis is important to access the desired molecules. We demonstrate a regiospecific annulation of unsymmetrically substituted 1,2‐di(arylethynyl)benzene derivatives for a geometry‐controlled synthesis of linear bispentalenes, which is one of the promising structures for material science. A gold‐catalyzed annulation of unsymmetrically substituted 1,2‐di(arylethynyl)benzene could produce two isomeric pentalenes, but both electronic and steric effects on the aromatics at the terminal position of the alkyne prove to be crucial for the selectivity; especially a regiospecific annulation was achieved with sterically blocked substituents; namely, 2,4,6‐trimetyl benzene or 2,4‐dimethyl benzene. This approach enables the geometrically controlled synthesis of linear bispentalenes from 1,2,4,5‐tetraethynylbenzene or 2,3,6,7‐tetraethynylnaphthalene. Moreover, the annulation of a series of tetraynes with a different substitution pattern regioselectively provided the bispentalene scaffolds. A computational study revealed that this is the result of a kinetic control induced by the bulky NHC ligands.
Funding
Australian Research Council
University of Wollongong
History
Publication title
Chemistry: A European JournalVolume
25Issue
52Pagination
12180-12186ISSN
0947-6539Department/School
School of Natural SciencesPublisher
Wiley-V C H Verlag GmbhPlace of publication
Po Box 10 11 61, Weinheim, Germany, D-69451Rights statement
Copyright 2019 the authors. Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) https://creativecommons.org/licenses/by-nc-nd/4.0/Repository Status
- Open