1-Tert-butyl 2-methyl pyrrolidine-1,2-dicarboxylate → 1-Boc-2-Formylpyrrolidine

온도

-78 °C

To a solution of pyrrolidine-1,2-dicarboxylic acid 1-tert-butyl ester 2-methyl ester (3.5 g) in toluene (40 mL) at −78° C. was added dropwise diisobutylaluminium hydride (20 mL of a 1.5 M solution in toluene) maintaining the temperature below −65° C. The reaction mixture was stirred at −78° C. for 2 hours and then quenched with methanol (10 mL). The mixture was then diluted with diethyl ether (50 mL), potassium sodium tartrate tetrahydrate was added and the mixture stirred vigorously for 20 min at room temperature. The two phases were then separated and the aqueous layer extracted with dichloromethane (2×50 mL). The combined organics were then washed with brine (100 mL), dried (MgSO4), reduced in vacuo and purified by column chromatography to give 2-formyl-pyrrolidine-1-carboxylic acid tert-butyl ester (2.68 g).

1. temperaturemaintaining the temperature below −65° C
2. customquenched with methanol (10 mL)
3. additionThe mixture was then diluted with diethyl ether (50 mL), potassium sodium tartrate tetrahydrate
4. additionwas added
5. stirringthe mixture stirred vigorously for 20 min at room temperature
6. customThe two phases were then separated
7. extractionthe aqueous layer extracted with dichloromethane (2×50 mL)
8. washThe combined organics were then washed with brine (100 mL)
9. dry with materialdried (MgSO4)
10. custompurified by column chromatography

ORD 기록

ord-0697efb82734472e963d7010a08ff016

출처 데이터셋

uspto-grants-2012_08

DOI

10.6084/m9.figshare.5104873.v1

특허 번호

US08252792B2