Formaldehyde → Methyl 3-dimethylamino-5-(methylthio)benzo[b]thiophene-2-carboxylate
Reaction equation
NC1C2C=C(SC)C=C[C:4]=2[S:5]C=1C(OC)=O.C=O.Cl[C:20]1[C:28]2[C:27]([N:29]([CH3:31])[CH3:30])=[C:26]([C:32]([O:34][CH3:35])=[O:33])[S:25][C:24]=2[CH:23]=[CH:22][CH:21]=1>>[CH3:30][N:29]([CH3:31])[C:27]1[C:28]2[CH:20]=[C:21]([S:5][CH3:4])[CH:22]=[CH:23][C:24]=2[S:25][C:26]=1[C:32]([O:34][CH3:35])=[O:33]Participants
4
Procedure
Prepared from methyl 3-amino-5-(methylthio)-benzo[b]thiophene-2-carboxylate by alkylation with formaldehyde as described in the preparation of methyl 4-chloro-3-(dimethylamino)benzo[b]thiophene-2-carboxylate. Yield 71% after recrystallization from ether-petroleum ether; mp=63°-66° C.