p-Toluenesulfonic acid → HCID 57659581, compound

Participants

Reaction Conditions

Reaction Steps

To the solution of 5-(2-benzyl-5-methyl-2H-pyrazol-3-yl)-2,2-dimethyl-[1,3]dioxane-4,6-dione obtained in step 1, pTsOH (3.74 g, 19.4 mmol) was added and stirring was continued for 2 h at 60° C. The reaction mixture was cooled to 0° C. and TEA (1.96 g, 19.4 mmol) was added drop by drop. Stirring was continued for 15 minutes. The mixture was concentrated under reduced pressure, the residue taken up into DCM (30 ml), washed with water (2×15 ml), dried over magnesium sulfate, filtered and concentrated under reduced pressure to give 1.03 g (96%) of (2-benzyl-5-methyl-2H-pyrazol-3-yl)-acetic acid methyl ester which was used in the next step without further purification. LC-MS: tR=0.83 min; [M+H]+=245.16.

Provenance & Evidence