Acetone → Methyl (1R,4S)-4-[(tert-butoxycarbonyl)amino]-1-(1-hydroxy-1-methylethyl)cyclopent-2-ene-1-carboxylate

温度

-78 °C

To a 1.00 M solution of lithium hexamethyldisilazide in tetrahydrofuran (45 mL) stirring at −78° C. was added a solution of methyl (1R,4S)-4-[(tert-butoxycarbonyl)amino]cyclopent-2-ene-1-carboxylate (5.0 g, 21 mmol) in tetrahydrofuran (40 mL). The resulting golden mixture was warmed to −28° C. to −23° C. (CCl4/dry ice) and stirred for 30 min. The reaction solution was cooled down to −78° C. and anhydrous acetone (1.8 mL, 25 mmol) was added. After the addition, the reaction mixture was kept in a CCl4/dry ice bath and allowed to warm to room temperature overnight. The dark solution was quenched with saturated NH4Cl and extracted with ether three times. The combined extracts were dried, filtered, concentrated. The crude residue was purified by flash column chromatography (EtOAc/Hexane) to yield the desired product (1.4 g, 22.6%).

1. additionAfter the addition
2. customthe reaction mixture was kept in a CCl4/dry ice bath
3. temperatureto warm to room temperature overnight
4. customThe dark solution was quenched with saturated NH4Cl
5. extractionextracted with ether three times
6. customThe combined extracts were dried
7. filtrationfiltered
8. concentrationconcentrated
9. customThe crude residue was purified by flash column chromatography (EtOAc/Hexane)

ORDレコード

ord-eafb2cef906f424dbdc33dc6cfdfca03

出典データセット

uspto-grants-2008_11

DOI

10.6084/m9.figshare.5104873.v1

特許番号

US07449467B2