Hydrochloric Acid → Benzene, (2,2-dichloro-1-methylcyclopropyl)-

Temperature

50 °C

A solution of 3 g of triethylbenzylammonium chloride in 500 g of chloroform is added over the course of 5 minutes to 800 g of 50% strength by weight sodium hydroxide solution in a 2 l stirred apparatus equipped with a dropping funnel and internal thermometer, at 50° C., whilst cooling and stirring slowly. A solution of 345 g of α-methylstyrene in 300 g of chloroform is added dropwise over the course of 45 minutes to the preceding mixture with vigorous stirring and cooling at 50° C. After stirring for a further 4 hours at 50° C., the reaction mixture is cooled to 20° C. and neutralised with concentrated hydrochloric acid at 10°-20° C., whilst cooling. It is then diluted with 2 l of water and the organic phase is separated off. The aqueous phase is extracted with 100 g of chloroform. The combined organic phases are washed with 250 g of water and 100 g of 10% strength by weight sodium carbonate solution. The solvent is then distilled off and the residue is subjected to fractional distillation. This gives 561 g=92.9% of theory of 2,2-dichloro-1-methyl-1-phenyl-cyclopropane of boiling point 116°-117° C./17 mm.

1. customequipped with a dropping funnel
2. stirringstirring slowly
3. stirringwith vigorous stirring
4. temperaturecooling at 50° C
5. stirringAfter stirring for a further 4 hours at 50° C.
6. temperaturewhilst cooling
7. customthe organic phase is separated off
8. extractionThe aqueous phase is extracted with 100 g of chloroform
9. washThe combined organic phases are washed with 250 g of water and 100 g of 10% strength by weight sodium carbonate solution
10. distillationThe solvent is then distilled off
11. distillationthe residue is subjected to fractional distillation

ORD record

ord-942fd1f17a9e4ab0996a3dc715a4ce24

Source dataset

uspto-grants-1983_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04396523