Potassium Hydroxide → 7-((5-Methyl-1H-imidazol-4-yl)methyl)-5,6,7,8-tetrahydroquinoline

Participants

Reaction Conditions

Reaction Steps

A mixture of (5) (0.83 g, 344 mmol), potassium hydroxide (0.782 g, 13.9 mmol), and hydrazine hydrate (0.77 mL, 24.7 mmol) in ethylene glycol (20 mL) was heated at 120° C. in an apparatus fitted with a Dean Stark trap for 1 h, and at 180° C. for 4 hours. The reaction was cooled to rt, and diluted with water. The aqueous medium was extracted three times with chloroform/isopropanol (3:1, 200 mL). The pooled organic layers were dried over magnesium sulfate. The mixture was filtered and the solvents were removed under vacuum. The residue was purified by chromatography on silica gel with 2 to 3% ammonia saturated methanol in dichloromethane to give 7-(5-methyl-1H-imidazol-4-ylmethyl)-5,6,7,8-tetrahydro-quinoline (6) as a foam (0.544 g, 2.40 mmol, 70% yield). 1H NMR (300 MHz, CDCl3): δ 8.30 (d, J=3.90 Hz, 1H), 7.43 (s, 1H), 7.37 (d, J=7.50 Hz, 1H), 7.03 (dd, J=7.50, 4.80 Hz, 1H), 2.99-2.91 (m, 1H), 2.84-2.76 (m, 2H), 2.70-2.50 (m, 3H), 2.24-2.14 (m, 1H), 2.15 (s, 3H), 2.04-1.96 (m, 1H), 1.54-1.40 (m, 1H).

Provenance & Evidence