Diisopropylethylamine → HCID 178516942, compound

Temperature

0 °C

To a suspension of thiophen-2-yl-methylamine (22.63 g, 200 mmol) and rhodanine (2-thio-4-thiazolin-4-one) (13.32 g, 100 mmol) in acetonitrile (200 mL) was added DIEA (N,N-diisopropylethylamine) (34.8 mL, 45.0 mmol) at room temperature. Then, it gave a clear solution within 2 min and this solution was cooled to 0° C. To this, mercuric chloride (27.15 g, 100 mmol) was added in three portions within a period of 15 min. After addition, the suspension was allowed to warm to room temperature and stirred for 2 days. The resulting black solids were filtered through a plug of celite and washed with dichloromethane (500 mL) and methanol (1.0 L). The combined solvents were removed under the vacuum and the crude residue was diluted with water (250 mL) and ethyl acetate (250 mL). The two layers were separated and the aqueous layer was extracted with dichloromethane (2×250 mL). The two organic extracts were washed separately with brine solution and dried over anhydrous magnesium sulfate. Filtration of the drying agent and removal of the solvent under the vacuum gave the crude solid. This solid was dissolved in acetonitrile (˜100 mL) at hot condition and then stored in the refrigerator overnight. The solids were collected by filtration and washed with cold acetonitrile (20 mL). After drying in air, 12.32 g (58% yield) of 2-[(thiophen-2-ylmethyl)-amino]-thiazol-4-one was isolated as a white amorphous solid: EI-HRMS m/e calcd for C8H8N2OS2 (M+) 212.0078, found 212.0083.

1. customThen, it gave a clear solution within 2 min
2. additionAfter addition
3. temperatureto warm to room temperature
4. filtrationThe resulting black solids were filtered through a plug of celite
5. washwashed with dichloromethane (500 mL) and methanol (1.0 L)
6. customThe combined solvents were removed under the vacuum
7. additionthe crude residue was diluted with water (250 mL) and ethyl acetate (250 mL)
8. customThe two layers were separated
9. extractionthe aqueous layer was extracted with dichloromethane (2×250 mL)
10. washThe two organic extracts were washed separately with brine solution
11. dry with materialdried over anhydrous magnesium sulfate
12. filtrationFiltration of the drying agent and removal of the solvent under the vacuum
13. customgave the crude solid
14. customstored in the refrigerator overnight
15. filtrationThe solids were collected by filtration
16. washwashed with cold acetonitrile (20 mL)
17. customAfter drying in air

ORD record

ord-028d4859b894464c816f9e30006d55bc

Source dataset

uspto-grants-2007_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07253285B2