Reaction #2298614

Reaction equation

ammonium formate

3-(formylamino)-4-methyl-2-thiophenecarboxylic acid methyl ester

3-(Formylamino)-4-methyl-2-thiophenecarboxylic acid methyl ester

→

7-methyl-3H-thieno[3,2-d]pyrimid-4-one

Yield 84.0%

Solvents

formamide

Conditions

Workup

1. 1
   OtherThe precipitate that formed
2. 2
   Filtrationwas collected by vacuum filtration

Procedure

To a solution of ammonium formate (5.1 g, 81 mmol) in formamide (25 mL) at 150° C. was added 3-(formylamino)-4-methyl-2-thiophenecarboxylic acid methyl ester (2, 5.0 g, 25 mmol) as a solid in small portions. The resulting solution was heated at 150° C. for 5 hours and then allowed to stand at room temperature for 12 hours. The precipitate that formed was collected by vacuum filtration to give 7-methyl-3H-thieno[3,2-d]pyrimid-4-one (3.4 g, 84% yield) as white needles.

Source