Phthalic Anhydride → 2-(4-hydroxy-2-oxoquinolin-1(2H)-yl)-1H-isoindole-1,3(2H)-dione

Participants

Reaction Conditions

Reaction Steps

A mixture of the product of Example 350A (0.54 g, 3 mmol), phthalic anhydride (1.36 g, 2.2 eq.) and diisopropylethylamine (1.97 g, 5 eq.) in dioxane (20 mL) was heated at 100° C. for 2 hours, cooled to 25C and concentrated. The residue was triturated with water and ether. The resulting solids were filtered and dried in vacuum to give the title compound (0.6 g, 64% crude yield) which was used directly for the next step. 1H NMR (300 MHz, DMSO-d6) δ 5.95 (s, 1H), 7.37 (m, 1H), 7.6 (m, 2H), 7.95-8.1 (m, 5H), 12.18 (s, 1H). MS (DCI+) m/z 306 (M+H)+.

Provenance & Evidence