Dimethyl Sulfate → (4-Chloro-1H-pyrrol-2-yl)acetonitrile

An aqueous solution of 114.0 g. of the product of Example VI is converted into the free base form by addition of 10% aqueous sodium hydroxide solution. The solid that is thus precipitated is filtered, washed with water and dried to give 67.1 g. (0.364 mole) of free base. The free base is dissolved in 350 ml. of dry dimethyl sulfoxide and stirred in an ice bath while 45.9 g. (0.364 mole) of dimethyl sulfate is added dropwise. The whole is then stirred for a half hour and warmed to room temperature, whereupon 20.0 g. (0.41 mole) of freshly ground and dried sodium cyanide is added all at once. After the resulting solution has been stirred for 2 hours at ambient temperature, it is poured onto ice and this aqueous solution is extracted four times with 250 ml. of diethyl ether. The combined ether extracts are washed successively with brine, 3N hydrochloric acid solution, aqueous sodium bicarbonate solution, and brine, and are dried over sodium sulfate. Evaporation of the ether yields 4-chloropyrrole-2 -acetonitrile as a brown oil.

1. customThe solid that is thus precipitated
2. filtrationis filtered
3. washwashed with water
4. customdried
5. customto give 67.1 g
6. dissolutionThe free base is dissolved in 350 ml
7. stirringAfter the resulting solution has been stirred for 2 hours at ambient temperature
8. additionit is poured onto ice
9. extractionthis aqueous solution is extracted four times with 250 ml
10. washThe combined ether extracts are washed successively with brine, 3N hydrochloric acid solution, aqueous sodium bicarbonate solution, and brine
11. dry with materialare dried over sodium sulfate
12. customEvaporation of the ether

ORD record

ord-05fbe0725d8b4c639fe5193262ab120a

Source dataset

uspto-grants-1977_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04048191