[C:1](N1C=CN=C1)(N1C=CN=C1)=[O:2].[CH3:13][C:14]([C:17]1[CH:18]=[C:19]([CH:24]=[C:25]([C:28]([CH3:31])([CH3:30])[CH3:29])[C:26]=1[OH:27])[C:20]([NH:22][NH2:23])=[O:21])([CH3:16])[CH3:15].C(N(CC)CC)C>O1CCCC1>[CH3:16][C:14]([C:17]1[CH:18]=[C:19]([C:20]2[O:21][C:1](=[O:2])[NH:23][N:22]=2)[CH:24]=[C:25]([C:28]([CH3:31])([CH3:30])[CH3:29])[C:26]=1[OH:27])([CH3:13])[CH3:15]1,1'-Carbonyl diimidazole (0.8 g, 0.005 mole) is added in one portion to a stirred 0° C. solution of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzoic acid hydrazide (1.0 g, 0.004 mole) and triethylamine (0.6 ml, 0.004 mole) in tetrahydrofuran (12 ml). After 18 hours the mixture is concentrated in vacuo and the residue dissolved in ether. The solution Is washed with aqueous 2M HCl, saturated aqueous NaHCO3, saturated aqueous NaCl, and dried over MgSO 4. Filtered and concentrated in vacuo to obtain a residue which is purified by flash chromatography using 10% ethyl acetate/hexane eluent. Recrystallize from ethyl acetate/hexane to obtain 0.6 g (1.1 g theor., 55%) 5-[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]-1,3,4-oxadiazol-2(3H)-one, mp 246° C.
Wird geladen…
