Methanol → Methyl 2-(5-bromopyridin-2-yl)acetate
반응식
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH2:8][C:9]([OH:11])=[O:10])=[N:6][CH:7]=1.S(Cl)(Cl)=O.[CH3:16]O>>[CH3:16][O:10][C:9](=[O:11])[CH2:8][C:5]1[CH:4]=[CH:3][C:2]([Br:1])=[CH:7][N:6]=1참가 물질
실험 절차
Key building block 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid (XII) can be prepared according to Scheme 8. Starting with commercially available 5-bromo-2-iodo-pyridine (XXXV), copper-catalyzed reaction with malonic acid diethyl ester furnishes 2-(5-bromo-pyridin-2-yl)-malonic acid diethyl ester (XXXVI). Hydrolysis and decarboxylation under basic conditions gives (5-bromo-pyridin-2-yl)-acetic acid (XXXVII), which subsequently can undergo nucleophilic acyl substitution with thionyl chloride in methanol to provide (5-bromo-pyridin-2-yl)-acetic acid methyl ester (XXXVIII). Deprotonation of XXXVIII with strong base followed by alkylation with 1-bromo-3-chloropropane gives 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid methyl ester (XXXIX), which can then be hydrolyzed under aqueous basic conditions to furnish key building block 2-(5-bromo-pyridin-2-yl)-5-chloro-pentanoic acid (XII).
후처리
- customHydrolysis and decarboxylation under basic conditions
출처 및 근거
- ORD 기록
- ord-44ba62b900434a189319d8b637d8c795
- 출처 데이터셋
- uspto-grants-2012_06
- 특허 번호
- US08202866B2
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