Trimethylsilyldiazomethane → Methyl indole-6-carboxylate

To a solution of indole-6-carboxylic acid (39.5 g, 245 mmol) in methanol (200 mL) and dichloromethane (750 mL) was added 2 M (trimethylsilyl)diazomethane in hexanes (160 mL, 320 mmol) dropwise over 1 hour. The reaction was stirred at room temperature overnight. The following day the reaction was concentrated to a thick brown crude oil that was diluted with ethyl acetate (500 mL) and washed with saturated aqueous sodium bicarbonate (2×200 mL), saturated aqueous sodium chloride (2×200 mL) and dried over sodium sulfate. The mixture was then filtered and the filtrate concentrated under reduced pressure to form a suspension. The suspension was filtered to provide 43 g of the desired compound as an off-white solid.

1. concentrationThe following day the reaction was concentrated to a thick brown crude oil that
2. additionwas diluted with ethyl acetate (500 mL)
3. washwashed with saturated aqueous sodium bicarbonate (2×200 mL), saturated aqueous sodium chloride (2×200 mL)
4. dry with materialdried over sodium sulfate
5. filtrationThe mixture was then filtered
6. concentrationthe filtrate concentrated under reduced pressure
7. customto form a suspension
8. filtrationThe suspension was filtered

ORD record

ord-69392822d2254edeb8c86a69e91e313c

Source dataset

uspto-grants-2004_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06743785B2