p-Toluenesulfonic acid → HCID 57628288, compound

Into a solution obtained by dissolving 3-aminothiophene (2.5 g, 25.2 mmol) in toluene (85.0 g), which was obtained by the method in Example 1 using methyl 3-aminothiophene-2-carboxylate as a starting material were added p-toluenesulfonic acid (0.2 g, 1.1 mmol) and 4-methyl-2-pentanone (100.0 g, 998.4 mmol) at room temperature, and the resulting solution was stirred under reflux under nitrogen atmosphere for 2 hours. The reaction solution was cooled to room temperature, and then washed with a 10% aqueous sodium hydroxide solution two times, and the obtained organic layer was concentrated under reduced pressure to give an oily substance. The resulting concentrate was purified by silica gel column chromatography to give 0.9 g of an oily substance as a mixture of three compounds including 3-amino-2-{(E)-(4-methyl-2-penten-2-yl)}thiophene, 3-amino-2-{(Z)-(4-methyl-2-penten-2-yl)}thiophene and 3-amino-2-(4-methyl-1-penten-2-yl)thiophene (yield: 19%).

1. temperatureunder reflux under nitrogen atmosphere for 2 hours
2. washwashed with a 10% aqueous sodium hydroxide solution two times
3. concentrationthe obtained organic layer was concentrated under reduced pressure
4. customto give an oily substance
5. concentrationThe resulting concentrate
6. customwas purified by silica gel column chromatography
7. customto give 0.9 g of an oily substance
8. additionas a mixture of three compounds

ORD record

ord-ffb37b06593b40e9b7826b030a7cfc8f

Source dataset

uspto-grants-2012_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08153823B2