Hydrochloric Acid → 3-Bromo-2-methyl-1-benzothiophene

Temperature

0 °C

To a solution of 15.88 g of 2,3-dibromobenzo[b]thiophene in 150 ml of dry diethyl ether at 0° C. was added a solution of 20 ml of diethyl ether and 34 ml of a 1.6M solution of n-butyl lithium in hexane. After stirring for one hour at 0° C., a solution of 10.2 ml of dimethylsulfate in 20 ml of diethyl ether was added and the reaction was stirred at 0° C. for 4 hours. The mixture was allowed to warm to room temperature. After the addition of 125 ml of 1N hydrochloric acid, the reaction mixture was stirred for 15 minutes. The layers were separated and the aqueous layer was extracted with diethyl ether. The combined ether extracts were dried over magnesium sulfate and evaporated in vacuo giving an oil. The oil was cooled and it solidified. The resulting crystals were recovered by filtration providing 8.7 g of the desired subtitled intermediate, m.p. 39°-40° C.

1. stirringthe reaction was stirred at 0° C. for 4 hours
2. temperatureto warm to room temperature
3. stirringthe reaction mixture was stirred for 15 minutes
4. customThe layers were separated
5. extractionthe aqueous layer was extracted with diethyl ether
6. dry with materialThe combined ether extracts were dried over magnesium sulfate
7. customevaporated in vacuo
8. customgiving an oil
9. temperatureThe oil was cooled
10. filtrationThe resulting crystals were recovered by filtration

ORD record

ord-b2df4408a423420895a6233e27705a98

Source dataset

uspto-grants-1987_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04659717