Reaction Steps
To a solution of 1-tert-butoxycarbonyl-1,2,3,4, -tetrahydro-2,2-dimethyl-4-quinolinone (EXAMPLE 325) (0.10 g, 0.36 mmol) and iodoethane (0.50 mL, 6.3 mmol) in DMF (5 mL) was added NaH (60% in mineral oil, 40 mg, 1.0 mmol) and the resulting mixture was stirred at rt for 15 h. The reaction was quenched with water (5 mL) and was extracted with EtOAc (2×15 mL). Removal of solvent and chromatography of the crude residue on a silica gel column using a 10% mixture of EtOAc and hexane as solvents afforded a mixture of products, which was treated with TFA (0.50 mL) in methylene chloride (1.0 mL) for 3 h. The reaction was neutralized to pH 10 by 5% NaOH and was extracted with EtOAc (2×20 mL). Chromatography (silica gel, EtOAc/hexane, 3/7) afforded 30 mg (41%) of (R/S)-3-ethyl-1,2,3,4-tetrahydro-2,2-dimethyl-4-quinolinone (30 mg, 0.15 mmol) as a colorless oil. The quinolinone (30 mg, 0.15 mmol) was treated with Et3SiH (1.0 mL) and BF3 -OEt2 (0.05 mL, 0.4 mmol) in CH2Cl2 (1.0 mL) at 100° C. for 15 h in a sealed tube. Purification of the crude product by chromatography (silica gel, EtOAc/hexane, 1/9) afforded 20 mg (71%) of (R/S)-3-ethyl-1,2,3,4,-tetrahydro-2,2-dimethylquinoline. Data for (R/S)-3-ethyl-1,2,3,4,-tetrahydro-2,2-dimethylquinoline: 1H NMR (400 MHz, CDCl3) 6.98 (d, J=7.5, 1H), 6.96 (t, J=7.5, 1H), 6.61 (t,J=7.5, 1H), 6.44 (d,J=7.5, 1H), 3.60 (s, 1H), 2.90 (dd, J=16.7, 5.2, 1H), 2.41 (dd, J=16.7, 10.7, 1H), 1.68 (m, 1H), 1.52 (m, 1H), 1.23 (m, 1H), 1.22 (s, 3H), 1.05 (s, 3H).
