Hydrochloric Acid → 4-Methoxy-3-methylsulfanylbenzoic acid

Triphenylphosphine (20.5 g; 78.2 mmol) was introduced a little at a time into a solution of 5c (5.1 g; 18.3 mmol) in toluene (50 ml). The reaction mixture was stirred at room temperature for 4.5 h. The precipitate (triphenylphosphine oxide) was filtered off, and the yellow filtrate was extracted with 10% strength aqueous sodium hydroxide solution (4×). Dimethyl sulfate (2 ml) was added to the combined aqueous extract, and the reaction mixture was stirred at room temperature for 2 h. The precipitate obtained was dissolved by heating to reflux temperature. The clear solution was cooled and adjusted to pH 1 using 20% strength hydrochloric acid. The precipitate (7c) was filtered off, washed with H2O and dried under reduced pressure over CaCl2.

1. filtrationThe precipitate (triphenylphosphine oxide) was filtered off
2. extractionthe yellow filtrate was extracted with 10% strength aqueous sodium hydroxide solution (4×)
3. additionDimethyl sulfate (2 ml) was added to the combined aqueous extract
4. stirringthe reaction mixture was stirred at room temperature for 2 h
5. customThe precipitate obtained
6. dissolutionwas dissolved
7. temperatureby heating
8. temperatureto reflux temperature
9. temperatureThe clear solution was cooled
10. filtrationThe precipitate (7c) was filtered off
11. washwashed with H2O
12. dry with materialdried under reduced pressure over CaCl2

ORD record

ord-5f8775898e70488e81a17644cb3c1060

Source dataset

uspto-grants-2009_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07582660B2