Amino-thienopyrimidine Series

 

This experiment is a scale up of previous reactions in the JRC 15-x series. The product of this experiment is a crucial intermediate toward analogues within the thienopyrimidine series. [b]Conclusion:[/b] Title compound synthesised in 40% purified yield. Methyl 3-aminothiophene-2-carboxylate (9.91 g, 63.0 mmol, 1 eq.), formic acid (2.51 mL, 66.5 mmol, 1.1 eq.) and ammonium formate (4.33 g, 68.7 mmol, 1.1 eq.) were dissolved in formamide (14.0 mL, 352 mmol, 5.6 eq). The mixture was heated at 140 °C for 72 h. The solution was allowed to cool to rt. A brown precipitate was formed, and collected by filtration. This brown substance was washed with chilled H2O to yield the title compound (by TLC) as brown crystals (8.7495 g, 57.49 mmol, 91%). These crystals were then washed with chilled EtOH/H2O to yield the title compound (by TLC) as brown crystals (3.916 g, 25.73 mmol, 40%). The filtrate was retained.