Welcome to chemicalbook!
Chinese English Japanese Germany Korea
400-158-6606
Try our best to find the right business for you.
Do not miss inquiry messages Please log in to view all inquiry messages.

Welcome back!

ChemicalBook CAS DataBase List Entacapone

Entacapone synthesis

10synthesis methods
-

Yield:130929-57-6 98%

Reaction Conditions:

Stage #1: (2E)-2-cyano-3-(3-methoxy-4-hydroxy-5-nitro-phenyl)-N,Ndiethylprop-2-enamidewith aluminum (III) chloride;triethylamine in dichloromethane at 0 - 5; for 3 - 4 h;Heating / reflux;
Stage #2: with hydrogenchloride in dichloromethane at 0 - 20; for 0.5 h;

Steps:

2 Preparation of N,N-diethyl-2-cyano-3-(3,4-dihydroxy-5-nitrophenyl)-acrylamide (entacapone); (I)

A round-bottom flask under nitrogen atmosphere is loaded with N,N-diethyl-2-cyano-3-(-3-methoxy-4-hydroxy-5-nitrophenyl-)-acrylamide (134 g, 0.421 mol) dissolved in dichloromethane (0.65 l) and triethylamine (128 g, 1.26 mol). The solution is cooled to 0-5° C. and aluminium trichloride (67.4 g, 0.505 mol) is added in portions. After that, the mixture is refluxed for 3-4 hours, until completion of the conversion. The reaction mixture is cooled to 0-5° C., a 20% hydrochloric acid solution (0.5 l) is dropped in the mixture, which is left under stirring at room temperature for 30 minutes. The resulting solid is filtered, washing with water (0.1 l×3), and dried in a static dryer under reduced pressure at 50° C.; 126 g are obtained. Yield: 98%.1H-NMR (300 MHz), δ (DMS0) 7.90 (d, 1H); 7.75 (d, 1H); 7.60 (s, 1H); 3.40 (m, 4H); 1.15 (m, 6H).

References:

US2008/146829,2008,A1 Location in patent:Page/Page column 4

Entacapone Related Search: