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ChemicalBook CAS DataBase List 4-(5-Nitro-pyridin-2-yloxy)-piperidine-1-carboxylic acid tert-butyl ester
346665-40-5

4-(5-Nitro-pyridin-2-yloxy)-piperidine-1-carboxylic acid tert-butyl ester synthesis

2synthesis methods
-

Yield:346665-40-5 99%

Reaction Conditions:

with di-isopropyl azodicarboxylate;triphenylphosphine in tetrahydrofuran at 20;Inert atmosphere;

Steps:

6.A A. 4-(5-Nitro-pyridin-2-yloxy)-piperidine-1-carboxylic acid tert-butyl ester, 6c

To a solution of 2-Hydroxy-5-nitropyridine (10 g, 69.24 mmol) in Tetrahydrofuran (350mL) at room temperature under nitrogen, 1-Boc-4-hydroxypiperidine (18.67 g, 90 mmol)and Triphenylphosphine (54.5 g, 207.7 mmol) were added. Finally DIAD (40.9 mL, 207.7mmol) was added dropwise and the mixture was stirred at room temperature overnight. The crude material was poured onto water/NaHCO3 and extracted with Ethyl acetate. The organic layer was dried over MgSO4, filtered and concentrated to dryness. The residue was purified by flash chromatography over silica gel (Ethyl acetate-heptane gradient from 5% to 30%). Pure fractions were combined, concentrated and dried under high vacuum togive the product (22.3 g, 99%). C15H22N305 MS m/z 224.2 (M-1OO+H).

References:

WO2017/123542,2017,A1 Location in patent:Page/Page column 213; 214

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