1550-35-2Relevant articles and documents
A Convenient Synthesis of Fluorobenzaldehydes by KF/Ph4PBr/18-Crown-6 Reagent System
Yoshida, Yasuo,Kimura, Yoshikazu
, p. 1355 - 1358 (1988)
4-Fluorobenzaldehyde was easily synthesized from 4-chlorobenzaldehyde by potassium fluoride in the presence of tetraphenylphosphonium halide plus 18-crown-6 or poly(ethylene glycol) dimethyl ether.Several fluorobenzaldehyde derivatives were similarly prepared from the corresponding chloro-derivatives in good yields.
Rhodium-catalyzed reductive carbonylation of aryl iodides to arylaldehydes with syngas
Chen, Suqing,Liu, Zhenghui,Mu, Tiancheng,Wang, Peng,Yan, Zhenzhong,Yu, Dongkun,Zhao, Xinhui
, p. 645 - 656 (2020/05/14)
The reductive carbonylation of aryl iodides to aryl aldehydes possesses broad application prospects. We present an efficient and facile Rh-based catalytic system composed of the commercially available Rh salt RhCl3·3H2O, PPh3 as phosphine ligand, and Et3N as the base, for the synthesis of arylaldehydes via the reductive carbonylation of aryl iodides with CO and H2 under relatively mild conditions with a broad substrate range affording the products in good to excellent yields. Systematic investigations were carried out to study the experimental parameters. We explored the optimal ratio of Rh salt and PPh3 ligand, substrate scope, carbonyl source and hydrogen source, and the reaction mechanism. Particularly, a scaled-up experiment indicated that the catalytic method could find valuable applications in industrial productions. The low gas pressure, cheap ligand and low metal dosage could significantly improve the practicability in both chemical researches and industrial applications.
Novel method for synthesizing dolutegravir key intermediate 2,4-difluorobenzylamine
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Paragraph 0029; 0031; 0032; 0035, (2018/11/22)
The invention discloses a novel production method which is concise and green in route, low in cost and easy to industrialize to prepare 2,4-difluorobenzylamine. The method comprises the following twosteps: a) at certain pressure, carrying out a carbonylation reaction on m-difluorobenzene and CO in the presence of a catalyst so as to generate 2,4-difluorobenzaldehyde, or carrying out a formylationreaction on m-difluorobenzene, namely carrying out chlorocarbene substitution on m-difluorobenzene in a chloroform strong base system, and further carrying out hydrolysis so as to prepare a product 2,4-difluorobenzaldehyde (Reimer-Tiemann reactions); b) putting the product 2,4-difluorobenzaldehyde of the step a) into an alcohol solvent, at certain pressure, in the presence of the catalyst, carrying out a reduction ammonolysis reaction on the component with an ammonia gas and hydrogen directly in the presence of a catalyst, or enabling the component to react with ammonium formate, thereby obtaining the 2,4-difluorobenzylamine. The preparation method disclosed by the invention is simple and easy in raw material obtaining, concise in route, green and environmentally friendly, low in cost andeasy in industrial production.