Reaktion #725862

Reaktionsgleichung

4-fluoroaniline

HCl

dimethyl dihydroxyfumarate

→

2,3-bis-(4-fluoroanilino)-but-2-enedioic acid dimethyl ester

Ausbeute 63.0%

Lösungsmittel

methyl alcohol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated
2. 2
   Temperaturto reflux for 3 hours
3. 3
   FiltrationThe next morning, the resulting thick paste was filtered on a coarse frit
4. 4
   Waschenwashed with a 50% (v:v) methanol-water mixture
5. 5
   Sonstigedried in a vacuum oven
6. 6
   Sonstigeyielding 32.4 g (63% yield) which
7. 7
   workup.ADDITIONa mixture of E/Z isomers (E:Z˜1:2)

Vorschrift

In a round bottom flask with a teflon stirbar, 25 g (142 mmol) of dimethyl dihydroxyfumarate (prepared according to a procedure described in U.S. Pat. No. 3,334,102), 34.7 g (312.5 mmol) of 4-fluoroaniline, 0.1 mL of concentrated HCl, and 90 ml of methyl alcohol were mixed and heated to reflux for 3 hours. The reaction mixture was cooled to room temperature and left overnight in a refrigerator. The next morning, the resulting thick paste was filtered on a coarse frit, washed with a 50% (v:v) methanol-water mixture, and dried in a vacuum oven, yielding 32.4 g (63% yield) which, according to NMR analysis, was a mixture of E/Z isomers (E:Z˜1:2).

Quelle