2024-03-28T09:47:38Z
https://soar-ir.repo.nii.ac.jp/oai
oai:soar-ir.repo.nii.ac.jp:00019892
2022-12-14T04:16:29Z
1169:1170
Synthesis of azulene-substituted benzofurans and isocoumarins via intramolecular cyclization of 1-ethynylazulenes, and their structural and optical properties
Shoji, Taku
Tanaka, Miwa
Takagaki, Sho
Miura, Kota
Ohta, Akira
Sekiguchi, Ryuta
Ito, Shunji
Moric, Shigeki
Okujima, Tetsuo
First published: 08 Dec 2017
The preparation of azulene-substituted benzofurans and isocoumarins was established by two types of intramolecular cyclization reaction of 1-ethynylazulenes. 2-(1-Azulenyl)- and 2,3-bis(1-azulenyl)benzofurans were prepared by the palladium-catalyzed cross-coupling reaction of 1-iodoazulenes with 2-ethynylphenol and that of 1-ethynylazulenes with 2-iodophenol under Sonogashira-Hagihara reaction conditions following the intramolecular nucleophilic addition of the oxygen nucleophile to the presumed 1-arylethynylazulenes. In contrast, 1-(phenylethynyl)azulenes bearing an o-methoxycarbonyl function on the substituted phenyl moiety exhibited intramolecular cyclization either in the presence of trifluoroacetic acid or N-iodosuccinimide (NIS) to afford azulene-substituted isocoumarins and 4-iodoisocoumarins, and the structures were clarified by single-crystal X-ray analysis. The optical properties of these compounds were also investigated by UV/vis spectroscopy and theoretical calculations.
Article
ORGANIC & BIOMOLECULAR CHEMISTRY. 16(3):480-489 (2018)
journal article
ROYAL SOC CHEMISTRY
2018-01-21
application/pdf
ORGANIC & BIOMOLECULAR CHEMISTRY
3
16
480
489
1477-0520
AA1168650X
https://soar-ir.repo.nii.ac.jp/record/19892/files/Org_Biomol_Chem_16_480-489.pdf
eng
29270584
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?CMD=search&DB=pubmed&term=29270584
10.1039/c7ob02861j
https://doi.org/10.1039/c7ob02861j
© 2017 Royal Society of Chemistry