Water → 5-(Chloromethyl)-2,2-difluorobenzo[d][1,3]dioxole

Temperature

20 °C

(2,2-difluoro-1,3-benzodioxol-5-yl)-methanol (1.0 eq) was dissolved in MTBE (5 vol). A catalytic amount of 4-(N,N-dimethyl)aminopyridine (DMAP) (1 mol %) was added and SOCl2 (1.2 eq) was added via addition funnel. The SOCl2 was added at a rate to maintain the temperature in the reactor at 15-25° C. The temperature was increased to 30° C. for 1 h, and then was cooled to 20° C. Water (4 vol) was added via addition funnel while maintaining the temperature at less than 30° C. After stirring for an additional 30 min, the layers were allowed to separate. The organic layer was stirred and 10% (w/v) aq NaOH (4.4 vol) was added. After stirring for 15 to 20 min, the layers were allowed to separate. The organic phase was then dried (Na2SO4), filtered, and concentrated to afford crude 5-chloromethyl-2,2-difluoro-1,3-benzodioxole that was used directly in the next step.

1. temperatureThe temperature was increased to 30° C. for 1 h
2. temperaturewas cooled to 20° C
3. temperaturewhile maintaining the temperature at less than 30° C
4. customto separate
5. stirringThe organic layer was stirred
6. addition10% (w/v) aq NaOH (4.4 vol) was added
7. stirringAfter stirring for 15 to 20 min
8. customto separate
9. dry with materialThe organic phase was then dried (Na2SO4)
10. filtrationfiltered
11. concentrationconcentrated

ORD record

ord-0c7af860c85048aa8f0f3599d255d600

Source dataset

uspto-grants-2016_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09241934B2