Water → methyl 2,3-dihydro-1H-indole-5-carboxylate

To a solution of 1H-Indole-5-carboxylic acid methyl ester (1 g, 5.71 mmol) in 10 mL of acetic acid at 0° C., was added sodium cyanoborohydride (1.08 g, 17.18 mmol) over 5 minutes. The mixture was stirred at room temperature for 1 h. Water (3 mL) was added and all the solvents were removed under vacuum. The residue was dissolved in ethyl acetate (150 mL) and saturated NaHCO3 (150 mL). The layers were separated and the aqueous layer was extracted with ethyl acetate (3×75 mL). The combined extracts were washed with brine (150 mL), dried, filtered and evaporated. The residue was purified by flash chromatography (0-50% ethyl acetate in hexane+0.1% triethylamine) to afford 0.99 g (99%) of 19a.

1. customall the solvents were removed under vacuum
2. dissolutionThe residue was dissolved in ethyl acetate (150 mL)
3. customThe layers were separated
4. extractionthe aqueous layer was extracted with ethyl acetate (3×75 mL)
5. washThe combined extracts were washed with brine (150 mL)
6. customdried
7. filtrationfiltered
8. customevaporated
9. customThe residue was purified by flash chromatography (0-50% ethyl acetate in hexane+0.1% triethylamine)

ORD record

ord-7823683c42df4aa780f9f24305922dc6

Source dataset

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08481731B2