
tasquinimod synthesis
- Product Name:tasquinimod
- CAS Number:254964-60-8
- Molecular formula:C20H17F3N2O4
- Molecular Weight:406.36

22864-65-9

248282-18-0

254964-60-8
General procedure for Example 8 N-methyl-N-(4-trifluoromethylphenyl)-1,2-dihydro-4-hydroxy-5-methoxy-1-methyl-2-oxoquinoline-3-carboxamide (Method B): 1,2-dihydro-4-hydroxy-5-methoxy-1-methyl-2-oxoquinoline-3-carboxylic acid (8 g, 0.032 mol) and triethylamine ( 15.5 ml, 0.11 mol) were dissolved in 10 ml of dichloromethane and cooled to 0°C. Within 0.5 h, 150 ml of a dichloromethane solution of thionyl chloride (3.0 ml, 0.042 mol) was added dropwise to this solution while maintaining the temperature at 4°C. After the dropwise addition, stirring was continued at 4°C for 4 hours. After completion of the reaction, the reaction mixture was diluted with 10 ml of dichloromethane and washed sequentially with cold 1 M sulfuric acid and 1 M sodium hydroxide solution. The pH of the aqueous phase was adjusted to 8-8.5, clarified by filtration and acidified with hydrochloric acid to pH 4. Upon standing, a crystalline precipitate was formed, the precipitate was collected by filtration, washed with water and dried to afford the target product 4-hydroxy-5-methoxy-N,1-dimethyl-2-oxo-N-(4-(trifluoromethyl)phenyl)-1,2-dihydroquinoline-3-carboxamide (8.5 g, 65% yield). The product was structurally confirmed by 1H NMR and 13C NMR and analyzed by ESI MS/MS.

1354639-61-4
15 suppliers
inquiry

22864-65-9
124 suppliers
$14.00/1g

254964-60-8
115 suppliers
$39.00/1mg
Yield: 99%
Reaction Conditions:
in octane for 2 h;Product distribution / selectivity;Reflux;Molecular sieve;
Steps:
4
A mixture of 11 (5.00 g, 18.9 mmol), N-methyl-p-trifluoromethylaniline (5.13 g, 28.4 mmol) and n-octane (200 mL) were refluxed in a Soxhlet extraction apparatus containing 4A molecular sieves (22.9 g) for 2 hours. After cooling the mixture the product was isolated as above to furnish 7.6 g (99 %) of 4-hydroxy-5-methoxy-N,l-dimethyl-2-oxo-N-[(4- trifluoromethyl)phenyl] - 1 ,2-dihydroquino line-3 -carboxamide (C) . 1 H-NMR analysis on the isolated product revealed no impurities other than 1 mol% remaining ester 11. 1 H-NMR (CDCI3) 9.9 (s, 1H), 7.50 (bs, 4H), 7.46 (t, 1H), 6.94 (d, 1H), 6.70 (d, 1H), 4.06 (s, 3H), 3.54 (s, 3H), 3.48 (s, 3H). When the same reaction was performed by the traditional distillation from n-octane (Entry 26) during 2 hours according to prior art US patent No. 6,875,869 the product was isolated in 94 % yield and determined by 1H-NMR analysis to consist of a mixture of compound C (96 mol%) and the starting material 11 (4 mol%).
References:
ACTIVE BIOTECH AB;BOCK, Lillemor Maria;HOLMBERG, Pär Henning;JANSSON, Karl-Erik WO2012/4338, 2012, A1 Location in patent:Page/Page column 13; 16

22864-65-9
124 suppliers
$14.00/1g

248282-18-0
11 suppliers
inquiry

254964-60-8
115 suppliers
$39.00/1mg

91105-97-4
32 suppliers
$45.00/10mg

254964-60-8
115 suppliers
$39.00/1mg

22864-65-9
124 suppliers
$14.00/1g

248282-13-5
14 suppliers
inquiry

254964-60-8
115 suppliers
$39.00/1mg

53600-33-2
211 suppliers
$10.00/1g

254964-60-8
115 suppliers
$39.00/1mg