Br[C:2]1[CH:7]=[CH:6][C:5]([CH:8]([CH3:10])[CH3:9])=[CH:4][C:3]=1[N+:11]([O-:13])=[O:12].[Cu][C:15]#[N:16]>CN(C)C=O.O.Cl.O.O.O.O.O.O.[Fe](Cl)(Cl)Cl>[CH:8]([C:5]1[CH:6]=[CH:7][C:2]([C:15]#[N:16])=[C:3]([N+:11]([O-:13])=[O:12])[CH:4]=1)([CH3:10])[CH3:9]
The product of Example 431A (0.581 g, 2.380 mmol) and copper (I) cyanide (0.426 g, 4.760 mmol) in N,N-dimethylformamide (5 mL) under a nitrogen atmosphere were heated in 160° oil bath for 1.5 hour. The reaction was cooled, treated with a solution of iron (III) chloride hexahydrate (2.48 g) in water (3.72 mL) and concentrated hydrochloric acid (0.62 mL), and then heated at 65° for 20 minutes. The cooled reaction mixture was extracted with ethyl ether (2×50 mL). The combined ethereal extracts were washed sequentially with 1N aqueous HCl (25 mL), 3N aqueous sodium hydroxide (25 mL), water (25 mL), and brine (25 mL) then dried over magnesium sulfate, filtered, and concentrated by rotary evaporation. Purification of the residue by silica gel flash chromatography eluting with 20:80 ethyl acetate/hexanes afforded the title compound as a yellow liquid (0.351 g, 1.845 mmol, 58%). 1H NMR (300 MHz, CHLOROFORM-D) δ ppm 1.33 (d, J=6.99 Hz, 6 H) 2.82-3.47 (m, 1 H) 7.66 (dd, J=7.91, 1.29 Hz, 1 H) 7.83 (d, J=7.72 Hz, 1 H) 8.18 (d, J=1.47 Hz, 1 H); MS (DCI) m/z 208 (M+NH4)+.
Wird geladen…
