Hydrochloric Acid → HCID 59905801, compound

Temperature

-30 °C

In a 250 mL dry RB flask, 4.50 mL of TiCl4 (40.8 mmol) was dissolved in 100 mL of CH2Cl2 and was cooled to −30° C. A solution of 2-[methoxycarbonyl-methyl-(2-trifluoromethyl-phenyl)-sulfamoyl]-benzoic acid methyl ester (8.0 g, 18.54 mmol) in 50 mL CH2Cl2 was added dropwise. The resulting solution was kept at −30° C. for 30 minutes and was then cooled to −78° C. Et3N (7.75 mL, 55.6 mmol) in 50 mL CH2Cl2 was slowly syringed in resulting a dark red solution. The reaction mixture was stirred at −78° C. for 4 hours and was then poured into a 1-L flask containing 250 mL of Et2O, 100 mL concentrated HCl, and 100 mL of H2O. The mixture was stirred at room temperature overnight. The layers were separated, and the organic layer was washed with brine and dried over MgSO4. Upon evaporation of the solvent, light yellowish crystals of 4-hydroxy-1,1-dioxo-2-(2-trifluoromethyl-phenyl)-1,2-dihydro-1λ6-benzo[e][1,2]thiazine-3-carboxylic acid methyl ester were formed. The product was collected through filtration and dried in oven to provide 2.2 g, 86% yield.

1. temperaturewas then cooled to −78° C
2. customin resulting a dark red solution
3. additionwas then poured into a 1-L flask
4. stirringThe mixture was stirred at room temperature overnight
5. customThe layers were separated
6. washthe organic layer was washed with brine
7. dry with materialdried over MgSO4
8. customUpon evaporation of the solvent, light yellowish crystals of 4-hydroxy-1,1-dioxo-2-(2-trifluoromethyl-phenyl)-1,2-dihydro-1λ6-benzo[e][1,2]thiazine-3-carboxylic acid methyl ester
9. customwere formed
10. filtrationThe product was collected through filtration
11. customdried in oven
12. customto provide 2.2 g, 86% yield

ORD record

ord-d0fb17ccb9ed49f2924047a5912615fd

Source dataset

uspto-grants-2003_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06545150B2