Diisopropylamine → HCID 22563241, compound

Temperature

-78 °C

n-Butyllithium (1.6M in hexane, 5.05 ml) was added dropwise to a solution of diisopropylamine (1.16 ml) in THF (30 ml) at 0° C. under argon. The resulting mixture was stirred for another 15 minutes before it was cooled to −78° C. and a solution of methyl isobutyrate (0.84 ml) in THF (3 ml) was added dropwise. After the addition was completed, the reaction mixture was allowed to warm to 0° C. and than again cooled to −78° C. At this temperature a solution of 4-chloromethyl-5-methyl-2-phenyl-oxazole [CAS 103788-61-0, commercially available] (1.17 g) in THF (6 ml) and DMPU (7.7 ml) was added. Stirring was continued for another 30 minutes before a saturated NH4Cl solution (1 ml) was added. Then the THF was removed in vacuo and water was added to the remaining residue. This mixture was extracted with ether and the combined organic extracts were washed with water and brine and dried (MgSO4). After evaporation of the solvent the crude alkylation product (1.46 g) was dissolved in THF (20 ml) and LiOH solution (1M, 14.5 ml) was added. The reaction mixture was stirred overnight, concentrated and washed with ether. Then the pH was adjusted to 1 by addition of 3N HCl and the resulting suspension was extracted with ether. Finally the combined extracts were washed with water and brine, dried (MgSO4) and the solvent was removed in vacuo. The product was obtained as a white solid (1.33 g).

1. additionAfter the addition
2. temperatureto warm to 0° C.
3. temperaturethan again cooled to −78° C
4. stirringStirring
5. additionwas added
6. customThen the THF was removed in vacuo and water
7. additionwas added to the remaining residue
8. extractionThis mixture was extracted with ether
9. washthe combined organic extracts were washed with water and brine
10. dry with materialdried (MgSO4)
11. customAfter evaporation of the solvent the crude alkylation product (1.46 g)
12. dissolutionwas dissolved in THF (20 ml)
13. additionLiOH solution (1M, 14.5 ml) was added
14. stirringThe reaction mixture was stirred overnight
15. concentrationconcentrated
16. washwashed with ether
17. additionThen the pH was adjusted to 1 by addition of 3N HCl
18. extractionthe resulting suspension was extracted with ether
19. washFinally the combined extracts were washed with water and brine
20. dry with materialdried (MgSO4)
21. customthe solvent was removed in vacuo

ORD record

ord-27c56853645d42bd9d0828d2d44bb487

Source dataset

uspto-grants-2008_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07314884B2