Methyl chloroglyoxylate → (3-Chloro-4-methylsulfanyl-phenyl)-oxo-acetic acid methyl ester

Temperature

0 °C

A solution of aluminum trichloride (54.9 g, 412 mmol) in chloroform (180 mL) under argon was cooled to 0° C. and then treated dropwise with a solution of methyl chlorooxoacetate (24.3 mL, 264 mmol) in chloroform (180 mL). The reaction mixture was stirred at 0° C. for 30 min and then was treated dropwise with a solution of 2-chlorothioanisole (39.4 g, 247 mmol) in chloroform (180 mL). The reaction mixture turned red in color. The resulting reaction mixture was allowed to warm to 25° C. where it was stirred for 4 h. The reaction mixture was then slowly poured onto ice (700 mL). The resulting yellow mixture was stirred for 15 min and then was filtered through celite to remove the aluminum salts. The filtrate was then extracted with methylene chloride (3×50 mL). The combined organic layers were washed with a saturated aqueous sodium bicarbonate solution (1×50 mL). The organic layer was then dried over magnesium sulfate, filtered, and concentrated in vacuo to afford (3-chloro-4-methylsulfanyl-phenyl)-oxo-acetic acid methyl ester (36.4 g, 60%) as a light yellow oil: EI-HRMS m/e calcd for C10H9ClO3S (M+) 243.9961, found 243.9958.

1. customThe resulting reaction mixture
2. temperatureto warm to 25° C. where it
3. stirringwas stirred for 4 h
4. additionThe reaction mixture was then slowly poured onto ice (700 mL)
5. stirringThe resulting yellow mixture was stirred for 15 min
6. filtrationwas filtered through celite
7. customto remove the aluminum salts
8. extractionThe filtrate was then extracted with methylene chloride (3×50 mL)
9. washThe combined organic layers were washed with a saturated aqueous sodium bicarbonate solution (1×50 mL)
10. dry with materialThe organic layer was then dried over magnesium sulfate
11. filtrationfiltered
12. concentrationconcentrated in vacuo

ORD record

ord-fc820bb9904a4945b6834b2180135da4

Source dataset

uspto-grants-2006_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07132425B2