反应详情

The product of Preparation 3 above, 3.6 g. of impure 6,6-dimethyl-1-dimethylamino-2-(3-trifluoromethylphenyl)-1-heptene-3,5-dione, was dissolved in 17 ml. of N,N-dimethylformamide dimethyl acetal and stirred under reflux at about 100° overnight using a sub-surface nitrogen bubbler. The mixture was then evaporated under vacuum to obtain 3.5 g. of a dark oil, which was dissolved in 120 ml. of tetrahydrofuran and reacted with 15 ml. of 40% aqueous methylamine at ambient temperature for 1 hour. The mixture was then evaporated under vacuum, and the resulting oil was chromatographed on a 300 g. silica gel column with 2:3 ethyl acetate:dichloromethane as the eluting solvent. The product-containing fractions was combined and evaporated under vacuum, and the residue was triturated under hexane to obtain 0.6 g. of the desired product, m.p. 86°-88°, showing the following peaks on nmr analysis in DMSOd6 : δ7.6-8.2 (m, 6H, aromatic); 3.8 (s, 3H, N--CH3); 1.2 (s, 9H, C(CH3)3).

1. customThe product of Preparation 3 above
2. temperatureunder reflux at about 100° overnight
3. customThe mixture was then evaporated under vacuum
4. customto obtain 3.5 g
5. dissolutionof a dark oil, which was dissolved in 120 ml
6. customThe mixture was then evaporated under vacuum
7. customthe resulting oil was chromatographed on a 300 g
8. customevaporated under vacuum
9. customthe residue was triturated under hexane
10. customto obtain 0.6 g