Tetrapropoxymethane → 3-Cyano-2-(1,1-dipropoxymethylenamino) thiophene
Reaktionsgleichung
[NH2:1][C:2]1[S:3][CH:4]=[CH:5][C:6]=1[C:7]#[N:8].[CH2:9]([O:12][C:13](OCCC)(OCCC)[O:14][CH2:15][CH2:16][CH3:17])[CH2:10][CH3:11]>C(O)CC>[C:7]([C:6]1[CH:5]=[CH:4][S:3][C:2]=1[N:1]=[C:13]([O:14][CH2:15][CH2:16][CH3:17])[O:12][CH2:9][CH2:10][CH3:11])#[N:8]Komponenten
4
Edukt 2
Produkt 1
Reagenzien, Katalysatoren, Lösungsmittel 1
Versuchsvorschrift
In a small distillation apparatus a mixture of 12.4 g(0.1 mol) 2-amino-3-cyanothiophene and 37.2 g (0.15 mol) tetra-n-propylorthocarbonate is heated for 3 hours at 155° C. n-PrOH, which arises during the reaction is directly distilled out of the reaction flask. After completion of the reaction, excess tetra-n-propylorthocarbonate is distilled off under reduced pressure and the resulting raw material purified by column chromatography over silica gel (eluant: hexane/tert.butylmethyl ether 6:1). Yield: 10.6 g of 3-cyano-2-(1,1-dipropoxymethyleneamino)thiophene in the form of slightly brownish crystals; m.p. 65-67° C.