7-Methylquinoline → 7-Methyl-2-phenylquinoline

Beteiligte Stoffe

Reaktionsschritte

To a solution of 7-methylquinoline (1.63 g, 11.4 mmol) in dry THF (10 mL), cooled by ice/water, was added phenyllithium (1.9 M in cyclohexane/ether 70/30, 6.0 mL, 11.4 mmol) dropwise over 5 min. After 15 min, the cooling bath was removed, and the solution was stirred at ambient temperature for 5 h. The reaction was quenched by adding MeOH, and stirring was continued overnight. Water was added, the mixture was extracted with EtOAc (3×35 mL), and the combined extracts were dried over MgSO4. The drying agent was filtered off, and air was bubbled into the solution for 7 d. The solvent was evaporated; the residue was dissolved in warm (≈50° C.) EtOAc/hexanes and filtered warm. The filtrate was concentrated and dried in vacuo, giving the crude title compound that was used directly for the next step. A sample was purified further by chromatography on silica gel (Jones Flashmaster, eluting with hexanes:EtOAc 3:1→2:1→1:1). 1H NMR (CDCl3, 400 MHz): δ=2.58 (s, 3H), 7.31 (d, J=3.7 Hz, 1H), 7.36-7.49 (m, 1H), 7.52 (t, J=8.0 Hz, 2H), 7.72 (d, J=8.2 Hz, 1H), 7.82 (d, J=8.2 Hz, 1H), 7.96 (s, 1H), 8.16 (t, J=8.0 Hz, 2H). MS (ES+): m/z 220.3 (100) [MH+]. HPLC: tR=2.7 min (Platform II, nonpolar—5 min).

Herkunft & Nachweise