Study On The Synthetic Technology Of Nerolidol From Linalool

The geranylacetone and the nerolidol were widely used in daily chemical industry, food industry, pharmaceutical industry and so on owing to its good characteristics, and they were also important intermediate on synthesis of squalene. The preparation of nerolidol from linalool was an important two step reaction on the synthetic route of squalene. As the limitation ways of obtaining squalence, it is meaningful to study the synthesis of squalen by chemical methods.Geranylacetone was synthesized from linalool and ethyl acetoacetate under catalyst presented. Aluminum isopropoxide, sodium dihydrogen phosphate, disodium hydrogen phosphate and sodium acetate were selected to catalyze the reaction based on analyzing mechanism of the reaction and the effect of the catalyst. The optimum conditions were determined by studying the effect of the material ratio, the reaction temperature, catalyst dosage and the reaction time. With the result of the orthogonal, the optimum technology conditions of different catalyst based on the single-factor experiment were as following:1. The optimum conditions of the reaction catalyzed by aluminum isopropoxide were: reaction temperature 170±2℃, molar ratio of linalool to acetoacetate 1:2, mass ratio of aluminum isopropoxide 1%(compared with linalool, the same below) and reaction time 8h. The influence order of the factors were:reaction temperature>molar ratio> amount of the catalyst> reaction time. The best yield was 77.9%.2. The optimum conditions of the reaction catalyzed by sodium dihydrogen phosphate were:reaction temperature 170±2℃, molar ratio of linalool to acetoacetate 1:2.2, mass ratio of sodium dihydrogen phosphate 3% and reaction time 8h. The influence order of the factors were:reaction temperature> reaction time> molar ratio> amount of the catalyst. The best yield was 78.8%.3. The optimum conditions of the reaction catalyzed by disodium hydrogen phosphate were:reaction temperature 170±2℃, molar ratio of linalool to acetoacetate 1:2, mass ratio of sodium dihydrogen phosphate 2.5% and reaction time 6h. The influence order of the factors were:reaction temperature> amount of the catalyst>molar ratio > reaction time. The best yield was 77.1%. 4. The optimum conditions of the reaction catalyzed by sodium acetate were:reaction temperature 175±2℃, molar ratio of linalool to acetoacetate 1:2.2, mass ratio of sodium dihydrogen phosphate 3% and reaction time 6h. The influence order of the factors were:reaction temperature> molar ratio> reaction time> amount of the catalyst. The best yield was 76.9%.Nerolidol was synthesized from geranylacetone and vinylmagnesium chloride by Grignard addition reaction and hydrolysis in acidic condition. The optimum conditions were determined by single-factor experiment and orthogonal test, and the optimum technology conditions were:molar ratio of geranylacetone to vinylmagnesium chloride 1:2.5, Grignard addition reaction temperature 55℃, Grignard addition reaction time 1.5h, hydrolysis reaction temperature 50℃, hydrolysis reaction time 3h, the concentration of the sulfuric acid 1.Omol/L, the molar ratio of sulfucic to geranylacetone 2:1, the mass ratio of THF to geranylacetone 5: 1. The influence order of the factors were:Grignard addition reaction time> concentration of the sulfuric acid>molar ratio>hydrolysis reaction time. The best yield was 58.2%.The preparation of nerolidol from linalool cataylyzed by solid superacid and cation exchange resin was studied in the thesis. The optimum technology conditions of the hydrolysis were:mass ratio of the water to the geranylacetone 10:1, mass ratio of the solid superacid to water 1:2, mass ratio of the cation exchange resin to water 1:5.