1426679-26-6Relevant articles and documents
A process for preparing 4 - (2 - hydroxyethyl) - 1, 3 - dihydro - 2H - indole -2 - one of the new method
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, (2019/04/04)
The invention discloses a novel method for preparing a ropinirole hydrochloride key intermediate 4-(2-ethoxy)-1,3-dihydro-2H-indole-2-ketone (I). The reaction process comprises the following steps of: carrying out reduction reaction on 2-methyl-3-nitrobenzene acetic acid (III) to generate 2-methyl-3-nitrobenzene ethanol (IV); protecting the hydroxyl of the compound (IV) to generate 2-methyl-3-(2-alkoxy ethyl) nitrobenzene (V); reacting the compound (V) with diethyl oxalate to generate a 2-nitro-6-(2-alkoxy ethyl)-phenyl acetyl formic acid compound (VI); reacting the compound (VI) with hydrogen peroxide to generate 2-nitro-6-(2-alkoxy ethyl)-phenylacetic acid (VII); and carrying out oxidation reaction on the compound (VII) to obtain 4-(2-ethoxy)-1,3-dihydro-2H-indole-2-ketone (I).
A new scalable route to 4-(2-hydroxyethyl)-1,3-dihydro-2 H-indol-2-one: A key intermediate for ropinirole hydrochloride
Chen, Huansheng,Chen, Yu,Yuan, Li,Zou, Qing
, p. 714 - 717 (2013/06/27)
A new and efficient manufacturing technology is disclosed in the present work for the preparation of 4-(2-hydroxyethyl)-1,3-dihydro-2H-indol-2-one, which is a key intermediate for ropinirole hydrochloride. The whole process gives the target molecule in 71% overall yield with 99% purity. In the final step, a novel nitro reduction/ring-closing/debenzylation takes place in one pot. All the intermediates can be used directly for the next step without purification in this process.