2-(2-tert-Butoxycarbonylamino-pyridin-4-ylmethylene)-succinic acid 4-benzyl ester 1-tert-butyl ester → 2-(2-Tert-butoxycarbonylamino-pyridin-4-ylmethyl)-succinic acid 1-tert-butyl ester

2-(2-tert-Butoxycarbonylamino-pyridin-4-ylmethylene)-succinic acid 4-benzyl ester 1-tert-butyl ester (2.81 g, 7.60 mmol) and Pd/C (10%, 400 mg) were suspended in EtOH and hydrogenated at 41 atm. and 28° C. for 3 days. The catalyst was removed from the reaction mixture by filtration. The catalyst was washed with EtOH (96%). 1 M K2CO3 (30 mL) was added to the filtrate followed by addition of water (50 mL). After 2 days the reaction mixture was evaporated to ca 80 mL, then brine (10 mL) was added and the reaction mixture extracted with ether. The aqueous phase was acidified to pH=3 and extracted with chloroform. Methanol (25 mL) was added and the reaction mixture was dried (Na2SO4+CaSO4) and filtered to give 2-(2-tert-butoxycarbonylamino-pyridin-4-ylmethyl)-succinic acid 1-tert-butyl ester (1.90 g, 83%).

1. customThe catalyst was removed from the reaction mixture by filtration
2. washThe catalyst was washed with EtOH (96%)
3. addition1 M K2CO3 (30 mL) was added to the filtrate
4. additionfollowed by addition of water (50 mL)
5. customAfter 2 days the reaction mixture was evaporated to ca 80 mL
6. additionbrine (10 mL) was added
7. extractionthe reaction mixture extracted with ether
8. extractionextracted with chloroform
9. additionMethanol (25 mL) was added
10. dry with materialthe reaction mixture was dried (Na2SO4+CaSO4)
11. filtrationfiltered

ORD-Eintrag

ord-00b62a1f34d149f5be38cda9b8af03bf

Quelldatensatz

uspto-grants-2008_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07423012B2