Reaktion #215910

Reaktionsgleichung

3-[(dimethylamino)methyl]-4-hydroxy-5-methoxybenzaldehyde

rhodanine

β-alanine

→

product

Ausbeute 74.5%

5-[[3-[(Dimethylamino)methyl]-4-hydroxy-5-methoxyphenyl]methylene]-2-thioxo-4-thiazolidinone

Ausbeute 74.5%

Lösungsmittel

acetic acid

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturheated to reflux
2. 2
   SonstigeAfter 4 hours the acetic acid is removed by rotary evaporator
3. 3
   workup.DISSOLUTIONthe residue dissolved in water (250 ml)
4. 4
   workup.ADDITIONThe solution is brought to approximate neutrality by addition of saturated aqueous sodium bicarbonate
5. 5
   workup.STIRRINGstirred for 3 hours
6. 6
   FiltrationThe precipitate is filtered off
7. 7
   Waschenrinsed three times with water
8. 8
   Sonstigedried
9. 9
   Sonstigetriturated
10. 10
    Temperaturcooled
11. 11
    Filtrationfiltered off
12. 12
    Sonstigedried

Vorschrift

A mixture of 3-[(dimethylamino)methyl]-4-hydroxy-5-methoxybenzaldehyde (2.5 g, 12 mmoles), rhodanine (1.6 g, 12 mmoles), β-alanine (0.6 g, 7 mmoles), and acetic acid (35 ml) is stirred under an inert atmosphere and heated to reflux. After 4 hours the acetic acid is removed by rotary evaporator and the residue dissolved in water (250 ml). The solution is brought to approximate neutrality by addition of saturated aqueous sodium bicarbonate, and stirred for 3 hours. The precipitate is filtered off, rinsed three times with water and dried, then triturated in boiling methanol (100 ml), cooled, filtered off and dried to afford the pure product (2.9 g), mp 198° C. (dec).

Quelle