Carbon Dioxide → 6-Methylhepta-3,5-dien-2-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 5.3 g of the aluminum tri(methyl acetylacetate) catalyst mentioned in Example 1 and 85 g of 1,2-propylene carbonate was heated to 170° C. and, at this temperature a mixture of 55 g (0.47 mol) of methyl acetoacetate and 43.7 g (0.52 mol) of 2-methyl-3-butyn-2-ol was metered in at a constant rate over the course of 4 h. After the addition was complete, the mixture was stirred at 170° C. for 30 min. During this time, CO2 was evolved and low boilers distilled out. The reaction mixture was subsequently cooled, and the 2-methyl-2,4-heptadien-6-one which was formed was distilled out under about 100 mbar. This resulted in 42 g of pure 2-methyl-2,4-heptadien-6-one, which corresponds to a yield of 72% of theory based on reacted 2-methyl-3-butyn-2-ol.

Herkunft & Nachweise