Ammonium thiocyanate → 2-(4-Fluorophenyl)acetyl isothiocyanate

Temperature

50 °C

To a solution of crude 1a (27.4 g, 159 mmol) from the previous step in MeCN (159 mL) was added ammonium thiocyanate (12.69 g, 167 mmol, 1.05 eq.). The fine yellow slurry was heated at 50° C. for 1 h. After cooling down to 0° C., the reaction mixture was filtered through a Celite pad and the cake was washed with MeCN (10 mL). The filtrate and washings were combined and concentrated to a volume of 30-40 mL, cooled again to 0° C. and filtered through a Celite pad. The cake was washed with MeCN (10 mL). The filtrate and washings were combined and concentrated to the same volume of 30-40 mL. The resultant solution contained 2-(4-fluorophenyl)acetyl isothiocyanate (2, assumed quantitative yield, Method B). Half of this solution was used in the next step.

1. temperatureAfter cooling down to 0° C.
2. filtrationthe reaction mixture was filtered through a Celite pad
3. washthe cake was washed with MeCN (10 mL)
4. concentrationconcentrated to a volume of 30-40 mL
5. temperaturecooled again to 0° C.
6. filtrationfiltered through a Celite pad
7. washThe cake was washed with MeCN (10 mL)
8. concentrationconcentrated to the same volume of 30-40 mL

ORD record

ord-171a27456a2142d3b5e7592731e7799d

Source dataset

uspto-grants-2013_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08569503B2