Study On The Synthesis And Application Of A New Amide Cooling Compound WS-2

This topic is mainly engaged in the synthesis of a new amide cooling compound WS-2(N-ethyl-2-isopropyl-2,3-dimethyl-butyric amide)and optimize the synthesis process to find out the best experimental approach.The article also carried out a test for the cooling effect of WS-2 and add the 2,3,4-trimethyl-3-pentanol to the perfume of toilet water as a cooling compound to find out the possibility of the application of the two products in the cosmetic.The synthesis of WS-2 is divided into four steps.The first step,methyl bromide was prepared by the reaction between hydrobomic acid and methanol, then it react with magnesium to form the Grignard reagent,then the diisopropyl ketone was added to react with it under ice bath to get the 2,3,4-trimethyl-3-pentanol.The crude product was distilled and purified by silica gel column chromatography,eluate V(ethyl acetate):V(petroleum ether)=4:1,the structure was identified to be correct by the IR,GC-MS and NMR.The second step, through the Koch-Haff reaction, the 2,3,4-trimethyl-3-pentanol was added dropwise to the solution which contains sulfuric acid and formic acid,stirred for three to five hours,the crude product was purified by low-temperature recrystallization and silica gel column chromatography,use bromocresol green as a color reagent and gradient elution, the eluateV(ethyl acetate):V(methanol)=4:1 and 2:1.The structure was identified to be correct by the IR, GC-MS and NMR.The third step, oxalyl chloride was added to the 2,3-dimethyl-2-propyl-butanoic acid dichloromethane solution with catalytic amount of DMF, refluied for 1h and the acyl chloride was received and identified to be correct by the IR and GC-MS.The fourth step, the triethylamine was added to the dichloromethane solution which contains ethylammonium chloride, stirred for half or one hour, then the acyl chloride was added dropwise and stirred for just two hours to get the WS-2, the structure was identified to be correct by the IR,GC-MS and NMR,the total yield is 35.6%.The article also study the application of 2,3,4-trimethyl-3-pentanol as a cooling compound in the perfume of toilet water and the cooling effect of WS-2. Through the study ,we found 2,3,4-trimethyl-3-pentanol is more adapted to the light perfume and its best dosage is 0.25 %. Through the cooling test of WS-2,we found that it has a high cooling activity.The temperatue drop of WS-2 in the 1,3-butanediol is up to 1.21K and 0.78K in the perfume.