Iodoethane → 7-Ethoxy-2,3-dihydro-1H-pyrrolo[1,2-a]indole

Temperature

0 °C

a solution of 64.00 g 2,3-dihydro-1H-3a-aza-cyclopenta[a]inden-6-ol in 240 mL N,N-dimethylformamide was added over 10 min to a cooled (0° C.) suspension of 17.73 g (0.406 mol) sodium hydride (55% in oil) in 400 mL N,N-dimethylformamide. The mixture was stirred at 0° C. for 30 min. To the resulting mixture was added 32.84 mL (63.39 g, 0.406mol) ethyl iodide dropwise over 10 min. The mixture was stirred at room temperature for 1 h. The mixture was partitioned between ice-water and ethyl acetate. The phases were separated and the organic phase was washed with 10% citric acid, 10% sodium bicarbonate solution and brine. The aqueous phases were re-extracted with ethyl acetate. The combined organic phases were dried over magnesium sulfate and evaporated to dryness. The solid residue was stirred with 600 mL n-hexane for 1 h and the product collected by filtration. The filtrate was concentrated to obtain a second crop of product, to afford a combined yield of 66.4 g (89.3%) of the title compound as white crystals melting at 101-102° C.

1. temperaturea cooled
2. stirringThe mixture was stirred at room temperature for 1 h
3. customThe mixture was partitioned between ice-water and ethyl acetate
4. customThe phases were separated
5. washthe organic phase was washed with 10% citric acid, 10% sodium bicarbonate solution and brine
6. extractionThe aqueous phases were re-extracted with ethyl acetate
7. dry with materialThe combined organic phases were dried over magnesium sulfate
8. customevaporated to dryness
9. stirringThe solid residue was stirred with 600 mL n-hexane for 1 h
10. filtrationthe product collected by filtration
11. concentrationThe filtrate was concentrated
12. customto obtain a second crop of product

ORD record

ord-5992f56d99c94de38229da6100c70f68

Source dataset

uspto-grants-2003_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06610685B2