120427-95-4Relevant articles and documents
Preparation method of 4-(2-bromoethyl)-1, 3-dihydro-2H-indole-2-ketone
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Paragraph 0032; 0035; 0036; 0040; 0043-0044; 0048; 0051-0052, (2021/05/05)
The invention provides a preparation method of 4-(2-bromoethyl)-1, 3-dihydro-2H-indole-2-ketone, and the preparation method of the 4-(2-bromoethyl)-1, 3-dihydro-2H-indole-2-ketone is characterized in that the 4-(2-bromoethyl)-1, 3-dihydro-2H-indole-2-ketone is prepared by taking o-bromoethyl benzaldehyde as an initial raw material and carrying out a series of reactions. The raw materials are cheap and easy to obtain, the product yield and purity are high, and the method has excellent economic and environment-friendly benefits.
Development of large-scale syntheses of ropinirole in the pursuit of a manufacturing process
Hayler, John D.,Howie, Simon L. B.,Giles, Robert G.,Negus, Alan,Oxley, Paul W.,Walsgrove, Timothy C.,Whiter
, p. 3 - 9 (2013/09/08)
Two plant syntheses of ropinirole {4-[2-(di-n-propyIamino)-ethyl]-1,3-dihydro-2H-indolin-2-one hydrochloride, SK&F-101468-A} using the ferric chloride mediated cyclisation of β-nitrostyrenes to form 3-chlorooxindoles as the key step are described. The first synthesis suffered the severe limitation of the final-step chemistry being nonselective in the reaction between di-n-propylamine and the bromide precursor to ropinirole as both substitution and elimination pathways were promoted and by-product formation at a level of 40% resulted. This problem was rectified in the latter synthesis by the more selective reaction between di-n-propylamine and the sulfonate ester precursor promoting ropinirole formation to a level of 88%. This second synthesis is now used as the commercial route, and problems (and their solutions) identified during the development of this route are now described. The identification of novel by-products which enabled the Sommelet oxidation step to be optimised is also reported. A unimolecular decomposition mechanism during hydrolysis of the hexaminium salt to form the key benzaldehyde intermediate is proposed and substantiated with experimental data.
Process for preparing substituted isoindolinone derivatives
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, (2008/06/13)
This invention relates to an improved process for the preparation of substituted indolinone derivatives using reductive cyclization conditions.