Diisopropylethylamine → (R)-(1-(4-fluorophenyl)-6-((4-(trifluoromethyl)phenyl)sulfonyl)-4,4a,5,6,7,8-hexahydro-1H-pyrazolo[3,4-g]isoquinolin-4a-yl)(thiazol-4-yl)methanone

Participants

Reaction Steps

A solution of (R)-tert-butyl 1-(4-fluorophenyl)-4a-(2-(trimethylsilyl)thiazole-4-carbonyl)-4a,5,7,8-tetrahydro-1H-pyrazolo[3,4-g]isoquinoline-6(4H)-carboxylate (76 mg, 0.103 mmol) in 4 M HCl/dioxane (3 mL) was stirred at room temperature for 1 hour. The solvent was removed in vacuo (azeotroping twice with toluene (˜4 mL)) to give a dark orange oil. This was dissolved in dichloromethane (3 mL) and 4-(trifluoromethyl)benzene-1-sulfonyl chloride (30.3 mg, 0.124 mmol) was added followed by diisopropylethylamine (90 μl, 0.516 mmol). The reaction mixture was stirred at room temperature for 0.5 hour. The solvent was removed in vacuo to give a dark orange oil. The crude product was purified by column chromatography on silica gel (gradient: 0-40% ethyl acetate in isohexane) to afford (R)-(1-(4-fluorophenyl)-6-((4-(trifluoromethyl)phenyl)sulfonyl)-4,4a,5,6,7,8-hexahydro-1H-pyrazolo[3,4-g]isoquinolin-4a-yl)(thiazol-4-yl)methanone as a white solid (44 mg). LCMS (Method F, ES-API): RT 2.65 min, m+H=589.2; 1H NMR (400 MHz, CDCl3): δ 8.86 (1H, d, J=2.1 Hz), 8.23 (1H, d, J=2.1 Hz), 7.84-7.82 (2H, m), 7.74-7.72 (2H, m), 7.45-7.40 (2H, m), 7.28 (1H, s), 7.19-7.13 (2H, m), 6.51 (1H, d, J=2.1 Hz), 5.48 (1H, dd, J=12.5, 2.1 Hz), 4.15 (1H, d, J=16.6 Hz), 3.92-3.87 (1H, m), 2.93-2.85 (2H, m), 2.72 (1H, d, J=12.6 Hz), 2.56-2.49 (2H, m).

Provenance & Evidence