[H-].C([Al+]CC(C)C)C(C)C.[C:11]([C:13]1[N:14]=[C:15]([C:21]2[CH:26]=[C:25]([Cl:27])[CH:24]=[C:23]([Cl:28])[C:22]=2[Cl:29])[C:16]([NH2:20])=[N:17][C:18]=1[NH2:19])#N.C[OH:31]>C1(C)C=CC=CC=1>[CH:11]([C:13]1[N:14]=[C:15]([C:21]2[CH:26]=[C:25]([Cl:27])[CH:24]=[C:23]([Cl:28])[C:22]=2[Cl:29])[C:16]([NH2:20])=[N:17][C:18]=1[NH2:19])=[O:31]Diisobutylaluminium hydride (1.5 M in toluene) (2.12 ml, 3.18×10−3 mole) was added dropwise at 0° C. under nitrogen to a suspension of 5-Cyano-2,6-Diamino-3-(2,3,5-trichlorophenyl)pyrazine (0.5 g, 1.59×10−3 mole) in dry toluene (70 ml) and the reaction was stirred at 0° C. for 1 hr. A further one equivalent of diisobutylaluminium hydride was then added and the mixture again stirred at 0° C. for 1 hr. Methanol (1 ml) was added carefully at 0° C. under nitrogen to destroy excess hydride and the reaction was warmed to room temperature. Ethyl acetate (100 ml) was added and the solution was washed with 5% citric acid solution (2×100 ml). The organic layer was separated, washed with brine (100 ml), dried over magnesium sulphate, filtered and the filtrate evaporated in vacuo to give the desired product. Yield 0.340 g (67%), N.m.r. (D6DMSO) δ: 7.53 (1H, d), 7.91 (1H, d), 6.90-7.80 (4H, b), 9.49 (1H, s).
Wird geladen…
