反应详情

温度

170 °C

A 5-L flask fitted with an overhead stirrer and a condenser was charged with di-n-butylamine (75 g) and acetic acid (70 g). Formaldehyde solution in water (1.3 L, 37%) was added and the resulting solution was heated to 50° C. with stirring. Pentanal (1 Kg) was then fed in over about 2 hours. After the feed was completed the temperature was maintained at 50° C. for 1 hour and then cooled to room temperature. The reaction mixture was poured into a separatory funnel. The organic layer was washed with water and purified by distillation to yield 2-methylene pentanal (820 g). 2-Methylene pentanal (302 g) and dicyclopentadiene (244 g) were loaded into a 2-L autoclave. The autoclave was sealed and heated to 170° C. The reaction was monitored by Gas Chromatography (“GC”) analysis, which showed the completion after 3 hours. The reaction was cooled to room temperature. The crude product was purified by distillation to yield 2-propylbicyclo[2.2.1]hept-5-ene-2-carbaldehyde (136 g). Product 2-methylene pentanal had the following NMR spectral characteristics:

1. customThe autoclave was sealed
2. customafter 3 hours
3. temperatureThe reaction was cooled to room temperature
4. distillationThe crude product was purified by distillation