Tetramethyltin → 5-Methyl-6-(trifluoromethyl)indoline

Temperature

110 °C

To a mixture of the trifluoromethylsulphonyloxyindoline (D6, 1.77 g, 4.69 mmol), lithium chloride (0.60 g, 14.1 mmol) and bis(triphenylphosphine) palladium (II) chloride (0.10 g, 0.14 mmol) in dry dimethylformamide (15 ml) was added tetramethyltin (0.72 ml, 5.2 mmol). The mixture was heated at 110° C. for 3.5 h, then cooled and evaporated. The residue was partitioned between dichloromethane and water, and the organic phase was washed with brine, dried and evaporated. The crude product was dissolved in ethanol (30 ml), 10% aqueous sodium hydroxide solution (7.5 ml) and solid sodium hydroxide (1 g) were added and the mixture was heated under reflux overnight. Ethanol was removed in vacuo, and the residue was diluted with water and extracted with dichloromethane. The organic extract was washed with brine, dried and evaporated. The residue was chromatographed on silica gel (50 g), eluted under suction with 2:1 ether/petroleum ether to give the title compound (0.70 g, 74%), m.p. 43-4° C.

1. temperaturecooled
2. customevaporated
3. customThe residue was partitioned between dichloromethane and water
4. washthe organic phase was washed with brine
5. customdried
6. customevaporated
7. dissolutionThe crude product was dissolved in ethanol (30 ml)
8. addition10% aqueous sodium hydroxide solution (7.5 ml) and solid sodium hydroxide (1 g) were added
9. temperaturethe mixture was heated
10. temperatureunder reflux overnight
11. customEthanol was removed in vacuo
12. additionthe residue was diluted with water
13. extractionextracted with dichloromethane
14. extractionThe organic extract
15. washwas washed with brine
16. customdried
17. customevaporated
18. customThe residue was chromatographed on silica gel (50 g)
19. washeluted under suction with 2:1 ether/petroleum ether

ORD record

ord-bf4f5ef73bcb4c01aee4357ffd368625

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06369060B1