23022-83-5Relevant articles and documents
Green synthesis method of bromoaromatic amine and alpha-bromoaromatic ketone
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Paragraph 0026-0029, (2017/07/21)
The invention discloses a green synthesis method of bromoaromatic amine and alpha-bromoaromatic ketone. The synthesis method comprises: adopting hydrobromic acid as a brominating agent, adopting 2-methylpyridine nitrate as a catalyst, and adopting molecular oxygen as an oxidizing agent, brominating an aromatic compound with a structure shown in formula (1) or aromatic ketone with a structure shown in formula (2) or (3), and preparing corresponding bromoaromatic amine or alpha-bromoaromatic ketone. The synthesis method is wide in substrate application reaction, high in atom utilization rate, capable of avoiding the application of the transitional metal element and volatile organic solvent and has the characteristics of economical efficiency and environmental protection. (Shown in the description).
A scalable procedure for light-induced benzylic brominations in continuous flow
Cantillo, David,De Frutos, Oscar,Rincon, Juan A.,Mateos, Carlos,Oliver Kappe
supporting information, p. 223 - 229 (2014/01/17)
A continuous-flow protocol for the bromination of benzylic compounds with N-bromosuccinimide (NBS) is presented. The radical reactions were activated with a readily available household compact fluorescent lamp (CFL) using a simple flow reactor design based on transparent fluorinated ethylene polymer (FEP) tubing. All of the reactions were carried out using acetonitrile as the solvent, thus avoiding hazardous chlorinated solvents such as CCl4. For each substrate, only 1.05 equiv of NBS was necessary to fully transform the benzylic starting material into the corresponding bromide. The general character of the procedure was demonstrated by brominating a diverse set of 19 substrates containing different functional groups. Good to excellent isolated yields were obtained in all cases. The novel flow protocol can be readily scaled to multigram quantities by operating the reactor for longer time periods (throughput 30 mmol h-1), which is not easily possible in batch photochemical reactors. The bromination protocol can also be performed with equal efficiency in a larger flow reactor utilizing a more powerful lamp. For the bromination of phenylacetone as a model, a productivity of 180 mmol h -1 for the desired bromide was achieved.
Silica sulfuric acid-promoted deacylation of α-bromo-β-diketones
Aoyama, Tadashi,Kubota, Sho,Takido, Toshio,Kodomari, Mitsuo
supporting information; experimental part, p. 484 - 485 (2011/06/25)
Novel deacylation of α-bromo-β-diketones using silica sulfuric acid (SSA) has been developed. Deacylation of 3- bromopentane-2,4-diones and 2-bromobutane-1,3-diones were carried out in the presence of SSA in dichloroethane under mild conditions to obtain the corresponding α-bromo ketones in good to excellent yields. SSA also promoted the FriedelCrafts type alkylation of benzene with 3-(sec-alkyl)-2,4-pentanediones to give the corresponding triarylmethanes in high yields in benzene.