Water → 2-[1-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl-methyl)-1H-pyrazol-3-yl]-isoindole-1,3-dione

Participants

Reaction Conditions

Reaction Steps

A mixture of 2-(1H-pyrazol-3-yl)-isoindole-1,3-dione (5.00 g, 23.5 mmol), 4-chloro-benzenesulfonic acid (S)-2,2-dimethyl-[1,3]dioxolan-4-yl-methyl ester (8.00 g, 26.1 mmol), and sodium t-butoxide (2.78 g, 28.9 mmol) in 1,4-dioxane (50 mL) was refluxed (103° C.) for 24 h. Upon cooling to 25° C., water (55 mL) was added. The mixture became cloudy and crystallization was observed. Then, water (50 mL) was slowly added over 30 min. Subsequent filtration, washing with water, and suction drying provided 2-[1-((R)-2,2-dimethyl-[1,3]dioxolan-4-yl-methyl)-1H-pyrazol-3-yl]-isoindole-1,3-dione (5.69 g, 74.1%) as an off-white solid: LR-ES-MS m/z calculated for C17H17N3O4 [M]+ 327, observed [M+H]+ 328.

Provenance & Evidence