Hydrochloric Acid → 4-methoxy-2,3-dihydro-1H-isoindole

Temperatur

0 °C

A stirred solution of 3-methoxyphthalimide (8.95 g, 50.56 mmol) in anhydrous tetrahydrofuran (200 ml) at 0° C. was treated dropwise with a solution of borane in tetrahydrofuran (1M, 150 ml, 0.15 mol) and the resulting mixture was stirred and held at reflux for 16 hours. The mixture was cooled to 0° C., methanol (60 ml) was added dropwise followed by 5M hydrochloric acid (60 ml) and the mixture was stirred and held at reflux for 4 hours. Upon cooling to room temperature the organic solvent was removed in vacuo and the mixture diluted with water (250 ml) and extracted with dichloromethane (3×250 ml). The aqueous layer was basified to pH 12 or above by the addition of 5M sodium hydroxide, extracted with dichloromethane (3×250 ml) and the combined extracts were evaporated to dryness M vacuo to afford 4-methoxyisoindoline (4.44 g, 59%) as a green oil which was used without further purification. 1H NMR (DMSO-d6) 7.18 (1H, t), 6.83 (1H, d), 6.78 (1H, d), 4.07 (2H, s), 4.02 (2H, s), 3.78 (3H, s). MS: [M+H]+ 150.

1. temperatureat reflux for 16 hours
2. stirringthe mixture was stirred
3. temperatureat reflux for 4 hours
4. temperatureUpon cooling to room temperature the organic solvent
5. customwas removed in vacuo
6. additionthe mixture diluted with water (250 ml)
7. extractionextracted with dichloromethane (3×250 ml)
8. additionThe aqueous layer was basified to pH 12 or above by the addition of 5M sodium hydroxide
9. extractionextracted with dichloromethane (3×250 ml)
10. customthe combined extracts were evaporated to dryness M vacuo

ORD-Eintrag

ord-4b52288e70be4c60ac7cecdc91d59e71

Quelldatensatz

uspto-grants-2012_01

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08106057B2