Trifluoroacetic acid → (+/-)-cis-6-(2,6-Difluorophenyl)-1,2,3,4,7b,8,9,10,11,11a-decahydro[1,4]diazepino[6,7,1-hi]pyrido[4,3-b]indole

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

tert-butyl (±)-cis-6-bromo-4-oxo-1,2,3,4,7b,10,11,11a-octahydro[1,4]diazepino[6,7,1-hi]pyrido[4,3-b]indol-9(8H)-carboxylate (500 mg, 1.19 mmol), triphenylphosphine (62 mg, 0.238 mmol), copper (I) bromide (34 mg, 0.238 mmol), and dichlorobis(triphenylphosphine)palladium (II) were dissolved in anhydrous N,N-dimethylformamide (20 ml) and degassed under nitrogen and stirred for 10 minutes. Then 2,6-difluorophenylstannane (1.5 eq, 497 mg) in anhydrous N,N-dimethylformamide (5 ml) was added via cannula and then heated to 60° C. for 30 minutes. Another portion of 2,6-difluorostannane (1.5 eq, 497 mg) in anhydrous N,N-dimethylformamide (2.5 ml) was added via cannula and then heated to 140° C. for 10 minutes. After 10 minutes a final portion of 2,6-difluorostannane (1.5 eq, 497 mg) in anhydrous N,N-dimethylformamide (2.5 ml) was added via cannula and reaction allowed to stir at 140° C. for 1 hour. The reaction was cooled to room temperature, diluted with ethyl acetate (200 ml) and washed with water (4×260 ml) and brine (2×150 ml). The organic layer was dried over magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure to give an oil. Purified oil via silica gel column chromatography, eluting with (10%) ethyl acetate in hexanes. Fractions were collected and concentrated under reduced pressure to give an oil. This oil was purified further by high pressure liquid chromatography on a Chiralcel OD column, eluted with 2% ethyl alcohol in hexanes (0.05% diethyl amine modifier) at 7 ml/min to afford a colorless oil. The oil was dissolved in chloroform (10 ml) and cooled to 0° C. in an ice bath and trifluoroacetic acid (2 ml) was added and stirred for 3 hours, during which time reaction warmed to room temperature. This was basified with concentrated ammonium hydroxide to pH 12, then extracted with chloroform (3×20 ml). Organics were seperated and washed with brine and dried over magnesium sulfate. Organics were filtered and then concentrated under reduced pressure to give the title compound as an oil (21 mg, 5%). 1H NMR(CDCl3, 300 MHz): δ 7.91 (d, 1H, J=1.5 Hz); 7.83 (s, 1H); 7.74 (s, 1H); 6.90 (t, 2H, J=8.1 Hz); 4.32 (t, 2H, J=9.6 Hz); 4.04 (t, 2H, J=9.54 Hz); 3.47 (s-broad, 2H); 3.31-3.04 (m, 3H); 3.08-3.04 (m, 1H); 2.23-2.10 (m, 1H); 2.08-2.03 (m, 1H) ppm.

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