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Methyl isoeugenol is an important synthetic flavors, carnation, rose, lilac, ylang ylang floral fragrance incense raw material, widely used in daily chemical flavor, food flavor and tobacco flavor. In this paper, eugenol as a starting material, dimethyl carbonate as methylating reagent, first by nucleophilic substitution reactions isoeugenol, under alkaline conditions, heterogeneous catalysis synthesis Methyl isoeugenol. Synthesized by liquid phase batch reaction the isoeugenol investigated the catalytic activity of the different types of solid alkali determine KF of a suitable catalyst. KF as a catalyst derived synthesis isoeugenol optimum conditions as follows: reaction temperature of 200 ° C, n (eugenol): n (DMC) = 1:2.5 KF amount of 10% by orthogonal experiment, the reaction time of 5.5 h. Under this condition, eugenol conversion rate of 98.9%, isoeugenol yield was 94.9%. Catalytic system KOH PEG-400, try isoeugenol methyl ether one step synthesis route, the study draws the optimum process conditions: reaction temperature of 200 ° C (eugenol): n (DMC) = 1:2, m (eugenol): m (KOH): m (PEG-400) = 1:0.14:0.06, reaction time 6 h. Methyl isoeugenol in this condition was 52% conversion rate of 97% of eugenol. Equal volume impregnation, activated alumina (γ-Al2CO3) as the carrier, the preparation of supported base catalyst. Investigation different alkali Immobilized on the catalytic activity of the catalyst in the gas-solid phase reaction to determine KOH/y-A12O3 (15 wt%) the best effect. To KOH/y-Al2O3 (15 wt%) as the catalyst, derived synthesis isoeugenol optimum conditions as follows: reaction temperature of 300 ° C and pressure of 1 MPa, the weight space velocity of 10 h-1, n (eugenol) : n (DMC) = 1:1.5. Under this condition, the conversion rate of 79% of eugenol, eugenol methylated product yield was 67%. Liquid PEG-400 and immobilized PEG-400 as a phase transfer catalyst, in the to catalytic isomerization prepared under solvent-free conditions isoeugenol ether. By orthogonal experiment, the optimum conditions for liquid PEG-400 catalyzed: m (isoeugenol, 81%): m (liquid PEG-400): m (KOH) = 1:0.16:0.12, reaction temperature 80 ℃, reaction time 3h. Methyl isoeugenol In this condition, the yield was 99.5%. Immobilized PEG-400 catalytic optimum conditions: m (isoeugenol, 81%): m (immobilized PEG-400): m (KOH) = 1:0.28:0.20, reaction temperature 90 ℃, reaction time 5 h. Methyl isoeugenol In this condition, the yield was 95.3%. Immobilized PEG-400 catalyst accumulated 8 cycles above, no decline in the yield.
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