Hydrochloric Acid → HCID 57682842, compound

3.94 g of AD-mix-β was added to a mixture consisting of 0.97 g of 8-allyl-7-methoxy-3-methyl-2H-1,3-benzoxazin-2,4(3H)-dione, 30 ml of tert-butanol, and 20 ml of water. The obtained mixture was stirred at room temperature overnight. Thereafter, 4.73 g of sodium sulfite was added to the reaction solution, and the obtained mixture was stirred for 50 minutes. The reaction solution was adjusted to be approximately pH 5 with addition of 1 N hydrochloric acid, and the reaction mixture was then extracted with ethyl acetate. The obtained organic layer was washed with a saturated sodium chloride solution and then dried over anhydrous magnesium sulfate. After removing the drying agent by filtration, the organic layer was concentrated under a reduced pressure. 8 ml of methanol and 4 ml of tetrahydrofuran were added to the obtained residue, and then, 1.44 ml of a 5 N sodium hydroxide aqueous solution was added thereto. The reaction mixture was then stirred for 10 minutes. The reaction solution was cooled on ice, and then 1 N hydrochloric acid was added thereto, so as to adjust pH to be approximately 6. Ethyl acetate was added to the reaction solution for extraction. The obtained organic layer was washed with a saturated sodium chloride solution and then dried over anhydrous magnesium sulfate. After removing the drying agent by filtration, the organic layer was concentrated under a reduced pressure, so as to obtain 0.81 g of the subject compound. It was observed as a mixture of two conformers in NMR. The ratio was approximately 2:1. The following measurement results are indicated with the number of hydrogen atoms such that the sum of conformers becomes a single molecule.

1. stirringthe obtained mixture was stirred for 50 minutes
2. extractionthe reaction mixture was then extracted with ethyl acetate
3. washThe obtained organic layer was washed with a saturated sodium chloride solution
4. dry with materialdried over anhydrous magnesium sulfate
5. customAfter removing the drying agent
6. filtrationby filtration
7. concentrationthe organic layer was concentrated under a reduced pressure
8. addition8 ml of methanol and 4 ml of tetrahydrofuran were added to the obtained residue
9. addition1.44 ml of a 5 N sodium hydroxide aqueous solution was added
10. stirringThe reaction mixture was then stirred for 10 minutes
11. temperatureThe reaction solution was cooled on ice
12. addition1 N hydrochloric acid was added
13. additionEthyl acetate was added to the reaction solution for extraction
14. washThe obtained organic layer was washed with a saturated sodium chloride solution
15. dry with materialdried over anhydrous magnesium sulfate
16. customAfter removing the drying agent
17. filtrationby filtration
18. concentrationthe organic layer was concentrated under a reduced pressure

ORD record

ord-275e308d9a2840fe8db8ae15735df71d

Source dataset

uspto-grants-2009_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07538123B2