Abstract
An efficient one-pot procedure for the direct catalytic synthesis
of substituted 2-aminothiophenes catalyzed by l -proline under
mild reaction conditions has been developed. A variety of functionalized
2-aminothiophene scaffolds were assembled in high yields by this
catalytic protocol. Low catalyst loading, simple procedure, and
high yields are the important attributes of this methodology.
Key words
Gewald reaction - 2-aminothiophene - one-pot - multicomponent - Knoevenagel reaction
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8
General Procedure
for the One-Pot Synthesis of Substituted 2-Aminothiophenes 3
l -proline (0.3 mmol), and DMF (3.0
mL) in a 50 mL round bottom flask was stirred at 60 ˚C for
10-24 h. The crude product was directly purified through flash
chromatography to give the desired product 3 .
The spectral data of all compounds 3a -o matched in all respects with reported
data.
