Water → 7-bromo-1,4,4,6-tetramethyl-3,4-dihydro-1H-quinoline-2-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of powdered potassium hydroxide (3.35 g, 59.67 mmol) in DMSO (40 mL) was stirred at 0° C. for 10 min. 7-bromo-4,4,6-trimethyl-3,4- dihydro-1H-quinoline-2-one (Example 1e) (8.0 g, 29.83 mmol) was added cautiously, followed immediately by the addition of ethyl iodide (12 mL, 149.17 mmol). The reaction mixture was kept at 0° C. for 30 min then slowly warmed up to room temperature and stirred overnight at room temperature. The reaction mixture was poured into water and extracted with dichloromethane washed with water and brine, dried (MgSO4), filtered and evaporated to give 8.8 g of 7-bromo-1,4,4,6-tetramethyl-3,4-dihydro-1H-quinoline-2-one and used without further purification in the Suzuki coupling (step a): 1H NMR (300 MHz; CDCl3): 1.24 (t, J=7.2 Hz, 1 H), 1.25 (s, 6 H), 2.37 (s, 3 H), 2.45 (s, 2 H), 3.98 (q, 2 H), 7.13 (s, 1 H), 7.18 (s, 1 H).

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