Lithium Hydroxide → 2-Tert-butoxy-2-[4-(2,4-dimethylphenyl)-7-[1-(2-hydroxyethyl)triazol-4-yl]-2-methyl-1-oxo-3-isoquinolyl]acetic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 2-(tert-butoxy)-2-(4-(2,4-dimethylphenyl)-7-ethynyl-2-methyl-1-oxo-1,2-dihydroisoquinolin-3-yl)acetate (26.0 mg, 0.060 mmol), 2-azidoethyl acetate (10.11 mg, 0.078 mmol), ascorbic acid (2.123 mg, 0.012 mmol) and copper sulfate monohydrate (1.923 mg, 0.012 mmol) in Ethanol (1.2 mL) and Water (0.2 mL) was irradiated in the microwave at 120° C. for 10 minutes. The mixture was diluted with ethyl acetate, then washed with saturated sodium bicarbonate and brine. The organic phase was dried over sodium sulfate, filtered and concentrated. The resulting crude residue in methanol (1.0 mL), tetrahydrofuran (THF) (1.0 mL) and water (0.2 mL) was treated with lithium hydroxide (28.8 mg, 1.205 mmol) and then heated to 60° C. for 90 minutes. The mixture was concentrated to dryness, water was added and the mixture was adjusted to pH 3-4 with 1N hydrochloric acid. The mixture was extracted with ethyl acetate; the extracts were washed with brine, dried over sodium sulfate, filtered and concentrated. The residue was purified by reverse phase chromatography to afford the desired product as a white solid. 1H NMR (400 MHz, CHLOROFORM-d) (atropisomers) δ=8.75-8.54 (m, 1 H), 8.14 (br. s., 2 H), 7.43 (d, J=7.6 Hz, 1 H), 7.15 (d, J=14.6 Hz, 2 H), 7.04-6.85 (m, 1 H), 5.44-5.15 (m, 1 H), 4.56 (m, 2 H), 4.14 (m, 2 H), 3.83-3.64 (m, 3 H), 2.43 (s, 3 H), 2.15-1.83 (m, 3 H), 1.29-0.97 (m, 9 H); LC/MS (m/z) ES+=505 (M+1).

Provenance & Evidence