HCID 58194817, compound → HCID 57399616, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-bromo-2-oxo-cyclohexanecarboxylic acid diethylamide (35; prepared according to Example 7(c)) (161 mg, 0.6 mmol) and (2-fluoro-ethyl)-(3-fluoro-phenyl)-amine (43) (184 mg, 1.2 mmol) was stirred under N2 at 50° C. for 3 h and the reaction turned brown. The resulting mixture was dissolved in propan-2-ol (1 mL) and dry zinc chloride (245 mg, 1.8 mmol) was added. The mixture was heated to reflux under N2 for 16 h and then concentrated in vacuo. The residue was dissolved in ethyl acetate (10 mL) and washed with 2 N HCl (5 mL), water (2×5 mL) and aqueous potassium carbonate solution (2×5 mL) then dried and concentrated in vacuo. The crude material was purified by semi preparative HPLC eluting with water (A) and methanol (B) (Gemini 5u, C18, 110A, 150×21 mm, 50-95% B over 20 min, 21 mL/min) to afford 20 mg (6%) of 7-fluoro-9-(2-fluoro-ethyl)-2,3,4,9-tetrahydro-1H-carbazole-4-carboxylic acid diethylamide as a white solid and 10 mg (3%) of 5-fluoro-9-(2-fluoro-ethyl)-2,3,4,9-tetrahydro-1H-carbazole-4-carboxylic acid diethylamide (non-radioactive imaging agent 10) as a white solid. The structure of 7-fluoro-9-(2-fluoro-ethyl)-2,3,4,9-tetrahydro-1H-carbazole-4-carboxylic acid diethylamide was confirmed by 1H NMR (300 MHz, CDCl3) δH 1.14 (3H, t, J=7 Hz, N(CH2CH3)2), 1.33 (3H, t, J=7 Hz, N(CH2CH3)2), 1.80-2.15 (4H, m, 2- and 3-CH2), 2.70-2.80 (2H, m, 1-CH2), 3.50-3.80 (4H, m, N(CH2CH3)2), 4.20-4.35 (1H, m, 4-CH), 4.40 (2H, dm, J=21 Hz, NCH2CH2F), 4.60 (2H, dm, J=41 Hz, NCH2CH2F), 6.70-6.80 (1H, m, NCCHCFCHCH), and 7.00-7.10 (2H, m, NCCHCFCHCH).

Provenance & Evidence