Synthesis of carbonylated heteroaromatic compounds via visible-light-driven intramolecular decarboxylative cyclization of o-alkynylated carboxylic acids
An efficient strategy for the easy access to carbonylated heteroaromatic compounds has been developed via a visible-light-promoted intramolecular decarboxylative cyclization reaction of o-alkynylated carboxylic acids. This method is characterized by its benign conditions and the tolerance to a wide range of functionalities.
[reaction: see text] A metalative 5-endo-dig cyclization reaction of 2-ynylphenoles or anilines effected by BuLi and ZnCl(2) produces 3-zinciobenzoheteroles in excellent yield. These intermediates have been transmetalated to the corresponding cuprates and allowed to react with electrophiles to produce a variety of 2,3-disubstituted benzofurans and indoles.
Nickel‐Catalyzed Acyl Group Transfer of
<i>o‐</i>
Alkynylphenol Esters Accompanied by C−O Bond Fission for Synthesis of Benzo[
<i>b</i>
]furan
作者:Ryohei Doi、Koji Shimizu、Yuma Ikemoto、Masashi Uchiyama、Mikiko Koshiba、Atsushi Furukawa、Katsumi Maenaka、Satoshi Watanabe、Yoshihiro Sato
DOI:10.1002/cctc.202001949
日期:2021.4.21
Herein, we report the nickel‐catalyzed cascade C−O bond cleavage/cyclization of ortho‐alkynylphenyl ester to construct a 3‐acylbenzo[b]furan skeleton. As a result of reaction condition screening, the Ni(0)/IAd (1,3‐Di(1‐adamantyl)imidazole‐2‐ylidene) system was found to be optimal for catalytic conversion. Interestingly, the reaction exclusively gives 3‐acylbenzo[b]furan instead of a decarbonylated
在此,我们报道了邻炔基苯基酯的镍催化级联C-O键裂解/环化反应,以构建3-酰基苯并[ b ]呋喃骨架。反应条件筛选的结果是,发现Ni(0)/ IAd(1,3-Di(1-金刚烷基)咪唑-2-亚基)体系最适合催化转化。有趣的是,该反应仅生成3-酰基苯并[ b用呋喃代替在羰基镍物种介导的反应中经常观察到的脱羰基产物。催化剂的负载量可以降低到5-10 mol%。我们证明了各种功能化的3酰基苯并呋喃衍生物的合成。我们进行了镍配合物的化学计量研究以及密度泛函理论(DFT)计算,以支持可能的反应机理。
Unexpected one-step synthesis of 3-benzoyl-2-phenylbenzofurans under Wittig conditions
作者:Michela Begala、Pierluigi Caboni、Maria João Matos、Giovanna Lucia Delogu
DOI:10.1016/j.tetlet.2018.03.048
日期:2018.5
conditions, led to 2-phenylbenzofuran derivatives 4a–p and the unexpectedformation of 3-benzoyl-2-phenylbenzofuran derivatives 5a–p. Benzoyl chlorides possessing electron-withdrawing groups afforded 3-benzoyl-2-phenylbenzofuran derivatives in higher yields than those with electron-donating groups. This reaction represents a simple and regioselective, one-pot route towards the preparation of deactivated
Unexpected detection of 3-aroylbenzofuran side products in the preparation of 2-arylbenzofurans: Identification, characterization, and comparison with chalcone's fragmentation patterns using EI/MS<sup>n</sup>
作者:Michela Begala、Giovanna Lucia Delogu
DOI:10.1002/jms.4425
日期:2019.9
ran, on the base of its mass spectrometric behaviour using a combination of electron ionization, exact mass measurement, multiple stage mass spectrometry, and labelled compounds. This study reports the common fragmentation pathways and discusses possible fragment structures of characteristic ions from a series of 3-aroyl-2-arylbenzofuran derivatives obtained as by-product under Wittig conditions. Emphasis