共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
The paramagnetic complexes formed in Friedel‐Crafts alkylation reaction systems are invistigated by electron spin resonance (ESR) spectroscopy, in room temperature ionic liquids system 1‐butyl‐3‐methyl‐limidazolium chloride‐aluminium chloride ([bmim]Cl‐AlCl3). The results indicate that ESR spectra observed are due to polycyclic aromatic radical cations formed from their parent hydrocarbons. ESR spectrum of spin adduct is obtained in an ionic liquid system composed of [bmim]Cl‐AlCl3. In acidic solution the 14N hyperfine coupling constant of 4‐oxo‐TEMPO, 2.15 mT, is appreciably larger due to an adduct formed with AlCl3. 相似文献
3.
4.
5.
3‐Phenylpropionanilide ( 4a ) is obtained in a yield of 89% from acrylanilide by the treatment with AlCl3/benzene, compared with a yield of 39% by the 1,4‐conjugate addition of phenyllithium. The formation of 4a indicated that an intermolecular Friedel‐Crafts reaction occurred, rather than the relatively more facile intramolecular ring cyclization, and provided a more efficient route than a conjugate addition of phenyllithium for the preparation of 3‐phenylpropionanilide and its derivatives. Although the methoxy group is an activator of the nucleophilic substitution, introduction of a methoxy substituent at N‐phenyl did not increase the competitive capability of the intramolecular cyclization because of AlCl3‐catalyzed demethylation to form the ArOAlCl2 complex which decreased the availability of the π‐electron in the N‐phenyl aromatic system. 相似文献
6.
7.
8.
9.
10.
11.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(8):2168-2171
Chiral fullerene–metal hybrids with complete control over the four stereogenic centers, including the absolute configuration of the metal atom, have been synthesized for the first time. The stereochemistry of the four chiral centers formed during [60]fullerene functionalization is the result of both the chiral catalysts employed and the diastereoselective addition of the metal complexes used (iridium, rhodium, or ruthenium). DFT calculations underpin the observed configurational stability at the metal center, which does not undergo an epimerization process. 相似文献
12.
13.
14.
15.
16.
17.
18.
Several substituted 4‐aroyl‐1‐indanones 2 and 5‐aroyl‐1‐tetralones 3 were prepared in good yields from 1‐indanones 1 via a series of reasonable transformations. 相似文献
19.