Cesium carbonate → 2-(2,4-Dimethoxyphenyl)-6-(4-methoxybenzylamino)-9-isopropylpurine

Participants

Reaction Conditions

Reaction Steps

Boronic Acid coupling reactions: A 10 mL flame-dried Schlenk flask equipped with a magnetic stir bar was charged with 2-chloro-6-(4-methoxybenzylamino)-9-isopropylpurine (0.193 g, 0.5 mmol, 1.0 equiv), 2,4-dimethoxyphenylboronic acid (0.136 g, 0.75 mmol, 1.5 equiv), Pd2(dba)3 (0.0069 g, 0.0075 mmol, 0.015 equiv.), ligand 1 (0.0051 g, 0.015 mmol, 0.03 equiv.) and Cs2CO3 (0.326 g, 1.0 mmol, 2.0 equiv.). The Schlenk flask was evacuated and backfilled with argon and charged with anhydrous 1,4-dioxane (2.0 mL). The reaction was stirred under argon at 80° C. and monitored by TLC. When the reaction was complete after 8 hours, the solvent was removed in vacuo and the reaction crude was purified by flash column chromatography (3% methanol in dichloromethane) to afford desired 2-(2,4-dimethoxyphenyl)-6-(4-methoxybenzylamino)-9-isopropylpurine (207 mg, 96%). 1H NMR (400 MHz, CDCl3) δ 1.59 (d, 6H, J=6.8 Hz), 3.79 (s, 3H), 3.84 (s, 3H), 3.85 (s, 3H), 4.87–4.96 (m, 3H), 6.14 (br, 1H), 6.57–6.60 (m, 2H), 6.85 (d, 2H, J=8.6 Hz), 7.34 (d, 2H, J=8.6 Hz), 7.73 (s, 1H), 7.78 (d, 1H, J=8.2 Hz); HRMS (MALDI-FTMS) [MH+] C24H28N5O3 434.2187, found: 434.2168.

Provenance & Evidence