Water → 136946-81-1

Temperature

-78 °C

Into a 2 litre two-necked round-bottomed flask, 50 g of indene (437 mmol) were dissolved under inert atmosphere with 500 ml of tetrahydrofuran and were cooled to −78° C. By slow dropping (1 hour) 175 ml of n-butyllithium (2.5 M in hexane, 437.5 mmol) were added. The mixture was allowed to heat up to room temperature and was kept under stirring for 4 hours. It was cooled to −78° C. and 40.42 g of dibromoethane (215 mmol) dissolved in 100 ml of tetrahydrofuran were dropped (within 20 minutes). After the end of the addition, the temperature was raised to 50° C., the whole was kept under stirring for 12 hours, then was cooled down to room temperature and 20 ml of water were added. The organic phase was dried and the residue was extracted with pentane. By evaporation under vacuum 28.65 g of product were obtained (yield=51.6%).

1. temperatureto heat up to room temperature
2. temperatureIt was cooled to −78° C.
3. additionwere dropped (within 20 minutes)
4. additionAfter the end of the addition
5. temperaturethe temperature was raised to 50° C.
6. stirringunder stirring for 12 hours
7. temperaturewas cooled down to room temperature
8. customThe organic phase was dried
9. extractionthe residue was extracted with pentane
10. customBy evaporation under vacuum 28.65 g of product
11. customwere obtained (yield=51.6%)

ORD record

ord-af527c53442d4dce9b3587935b038a1c

Source dataset

uspto-grants-2002_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06423660B1