Hydrochloric Acid → 3-(4,6-diethoxy-1,3,5-triazin-2-yl)-1-[(difluoromethyl)sulfonyl]-7-fluoro-1,3-dihydro-2H-indol-2-one

Participants

Reaction Conditions

Reaction Steps

3-(4,6-Diethoxy-1,3,5-triazin-2-yl)-7-fluoro-1,3-dihydro-2H-indol-2-one (1.0 g) and 1-methyl-1H-imidazole (0.51 g) are introduced as initial charge in 10 ml of dichloromethane and cooled to 0° C. under nitrogen. With stirring, difluoromethanesulfonyl chloride (0.46 g) is added dropwise and the mixture is after-stirred for 2 hours at 0° C. to 6° C. After adding 1-methyl-1H-imidazole (0.25 g) and difluoromethanesulfonyl chloride (0.23 g), the mixture is stirred for 2 hours at 0° C. to 10° C. After adding 5 ml of water, the mixture is adjusted to pH 2 using 10% strength hydrochloric acid, the organic solvent is largely distilled off in vacuo, and the solid is filtered off, washed with water and heptane and dried. This gives the title compound as a solid in an HPLC purity of 93% (1.19 g, 83% of theory). The UV absorption (maximum at 360 nm) verifies the N-sulfonylation of the product.

Provenance & Evidence