Dimethyl Disulfide → 6-(Methylsulfanyl)-1H-indole

Temperature

-78 °C

To a solution of 6-bromo-1H-indole (5 g, 25.50 mmol) in anhydrous THF (60 mL) at 0° C. was added KH (6.80 g, 51.00 mmol, 30% wt in mineral oil). After stirring for 30 min and cooling to −78° C., t-BuLi (39.23 mL, 51.0 mmol, 1.3 M) was added to the formed mixture under nitrogen. After 30 min, 1,2-dimethyldisulfane (4.80 g, 51.0 mmol) was added to the formed mixture. The reaction mixture was stirred at −78° C. for 1 h. The mixture was quenched with sat. NH4Cl (30 mL) at −78° C. slowly (Caution: flame), adjusted pH=7 with 1 N aqueous phosphoric acid and extracted with EtOAc (50 mL×3). The combined organic layers were dried over anhydrous sodium sulfate, filtered, concentrated and purified by column chromatography on silica gel eluted with PE/EtOAc 10:1 to give 6-(methylthio)-1H-indole (3.9 g, 93.67% yield) as a grey solid. LC-MS MS (ESI) m/z 164.1 [M+H]+. 1H NMR (CDCl3 400 MHz): δ 8.14 (brs, 1H), 7.56 (d, J=8.0 Hz, 1H), 7.37 (s, 1H), 7.18-7.11 (m, 1H), 6.56-6.51 (m, 1H), 2.52 (s, 3H).

1. waitAfter 30 min
2. stirringThe reaction mixture was stirred at −78° C. for 1 h
3. customThe mixture was quenched with sat. NH4Cl (30 mL) at −78° C.
4. temperatureslowly (Caution: flame)
5. extractionextracted with EtOAc (50 mL×3)
6. dry with materialThe combined organic layers were dried over anhydrous sodium sulfate
7. filtrationfiltered
8. concentrationconcentrated
9. custompurified by column chromatography on silica gel
10. washeluted with PE/EtOAc 10:1

ORD record

ord-cd448e97124e40c6b97b8f7d7687faa1

Source dataset

uspto-grants-2016_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09416135B2