622-60-6Relevant articles and documents
Hydrosilylation of aromatic azomethines
Zuev,Kovaleva,Skvortsov
, p. 548 - 550 (2004)
The reactions of aromatic azomethines with methyldichlorosilane, phenyldichlorosilane, and dimethylchlorosilane, performed in the presence of Speier's, Wilkinson's, and Karstedt's catalysts and a series of Pt(II) complexes LL'PtCl2, give hydrosilylation and reduction products whose ratio depends on the catalyst used. The highest yield of hydrosilylation products is attained with Pt(II) complexes as catalysts.
A new alkylation of aryl alcohols by boron trifluoride etherate
Jumbam, Ndze Denis,Maganga, Yamkela,Masamba, Wayiza,Mbunye, Nomthandazo I.,Mgoqi, Esethu,Mtwa, Sphumusa
, (2019/10/28)
The ethylation of aryl alcohols by an ethyl moiety of boron trifluoride etherate is described. The reaction proceeded cleanly and afforded good yields of the corresponding aryl ethyl ethers. It tolerated the presence of functional groups such as aryl, alkyl, halogens, nitro, nitrile, and amino. However, the presence of amino or nitro groups ortho to a hydroxyl group of an aryl compound drastically reduced the yields of the anticipated products due to the chelation of the aforementioned functional groups with boron trifluoride etherate. A nitrogen atom in the aromatic ring system, as exemplified by hydroxypyridine and 8-hydroxyquinoline, completely inhibited the reaction. Resorcinol, hydroquinone, and aryl alcohols with aldehyde functions decomposed under the reaction conditions.
Preparation method of dapagliflozin intermediate
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Paragraph 0022; 0023; 0024; 0025, (2018/03/01)
The invention provides a preparation method of a dapagliflozin intermediate. The preparation method comprises the following steps: (1) by taking 4-methylphenol and bromoethane as raw materials, a polar solvent as a reaction solvent and an inorganic base as a catalyst, carrying out reaction for preparing 4-ethyoxyl methylbenzene; (2) by taking N-chlorosuccinimide and 4-ethyoxyl methylbenzene obtained in the step (1) as raw materials, a non-polar solvent as a reaction solvent and dibenzoyl peroxide as an initiator, carrying out reaction, thus obtaining 4-ethyoxyl benzyl chloride; (3) dissolving 4-ethyoxyl benzyl chloride obtained in the step (2) and 4-bromaniline into ethyl acetate, adding a catalyst lewis acid, and carrying out reaction, thus obtaining 5-bromo-2-amino-4-ethyoxyl diphenylmethane; and (4) carrying out diazotization reaction on 5-bromo-2-amino-4-ethyoxyl diphenylmethane obtained in the step (3), and then reacting with cuprous chloride, thus synthesizing 5-bromo-2-chloro-4'-ethyoxyl diphenylmethane. The preparation method provided by the invention has the advantages of low cost, low environmental stress and short synthetic route.
