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Synthesis of aromatic aldehydes selected Gattermann-Koch synthesis of 2,4,6 - trimethylbenzaldehyde the 2,4,5 - trimethylbenzaldehyde , 5,6,7,8 - tetrahydronaphthalene-2 - formaldehyde , and 3,4 - dimethoxy benzaldehyde . Low molecular weight gelator overview of the proposed new method , and categorized the proposed design of the gelator basic rules . Optimized the 2,4,6 - trimethylphenoxy formaldehyde and 3,4 - dimethylbenzaldehyde synthesis conditions . 3,4 - the synthesis dimethylbenzaldehyde the optimum conditions are as follows : reaction temperature of 0? C, CO pressure 1.0 to 0.6MPa , the amount of concentrated hydrochloric acid is about 0.024mol concentrated hydrochloric acid / 1.0 mol of AlCl3 , o-xylene with anhydrous AlCl3 molar ratio is 5.0:1.0 , and the reaction 15h, yield 91.5% . Trace aldehyde skip can accelerate the reaction and are able to slightly increase the yield, atmospheric Gattermann-Koch method of aldehyde synthesis HCl gas may be replaced with a catalytic amount of concentrated hydrochloric acid . 2,4,6 - the synthesis trimethylbenzaldehyde the optimum conditions as follows: reaction temperature of 26 to 28 ° C , the CO pressure 1.06 to 1.48MPa , the amount of concentrated hydrochloric acid is about 0.037mol concentrated hydrochloric acid / 1.0molAlCl3 mesitylene with anhydrous AlCl3 molar ratio of 3.08:1 of AlCl3 containing 2.2% (wt) TiCl4, for 28h, a yield of 86.9% . Found that the the cocatalyst TiCl4 can increase the yield , trace isopropyl ether added to the reaction time can be greatly reduced , the catalytic effect of the Industrial aluminum trichloride best . Gattermann-Koch pressureless reaction and the HF-BF3 catalyzed Gattermann-Koch reaction , some exploration, and found that the synthesis of 3,4 - dimethylbenzaldehyde at atmospheric pressure , HCl gas can be replaced with a catalytic amount of concentrated hydrochloric acid . Sorbitol acetal compound was synthesized using the above - described synthesis of aromatic aldehydes , testing the performance of the gel , and the substituent on the benzene ring on the gel properties of the sorbitol acetal compound very significant discovery 1,3:2 , 4 - bis ( 2,4,5 - tri -methylbenzylidene )-D- sorbitol is not gel properties , 1,3:2,4 - bis ( 5,6,7,8 - tetrahydronaphthalene -2 - sub - methylene )-D- sorbitol good gelling properties of the non - polar compounds . 12 urea and urethane compounds was designed and synthesized , tested the gel properties , the compound 15,16,17,18 also has good gelling properties .
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