Study On Synthesis Of New Latent Fragrant Pyrazine Derivatives And Application In Cigarette

With α-Amino acids and perfume alcohol,13kinds of Pyrazinamide compounds and12kinds ofPyrazine Esters were synthesized via the acylation and esterification reaction using2,3-Pyrazinedicarboxylic acid and2,3,5,6-tetramethyl Pyrazine as raw materials.22kinds of them were newcompounds, and the optimal reaction conditions for the synthesis of target products werediscussed. The structures of synthesized coumponds were confirmed by IR,1H NMR,13C NMR,HRMS and X-ray single crystal diffractometer (XRD). The thermal gravimetric analysis, pyrolysisand application in cigarette of the products were researched. The main research contents are asfollows.1. Using2,3-Pyrazine dicarboxylic acid as raw material,7kinds of N-(formylpyrazine)-α-Aminoacid methyl esters and6kinds of2,3-pyrazinedicarboxylic acid dialcohol ester derivatives weresynthesized via the acylation and esterification reaction, and the most optimal reaction conditionswere also discussed. The results showing:1) two different types of pyrazinamide derivatives weresynthesized via two methods of One-step and Fractional steps under the action of thionyl chloride.The optimum reaction conditions: in the stepwise, the after-treatment of2,3-pyrazine dicarboxylicchloride hydrochloride was to use direct filtration and the amount of Et3N was1.5mL. In theone-step, the amount of Et3N was1mL, and thionyl chloride was6mL.2)Using DCC/DMAPcatalyzed esterification, pyrazine ester derivatives were synthesized. In order to achieve thepurification products, put the ether to except DUP the by-product of DCC in the after-treatment.2. Using2,3,5,6-tetramethyl pyrazine as raw material,3,6-dimethyl-2,5-pyrazinedicarboxylic acidwas synthesized under the oxidation of KMnO4and concentrated H2S04. By reaction with SOCl2,the resulting material reacted with amino acid methyl ester hydrochlorides, and flavor alcohols,respectively, and6kinds of pyrazinamide compounds and6kinds of pyrazine ester derivativeswere obtained.3. With selecting the portion of the target products as representatives, the pyrolysis behavior ofpyrazine derivatives was explored under three temperature of300℃,600℃and900℃. Qualitativeof pyrolysis products was analyzed with NIST05a.L mass library retrieving. The relativequantitative of pyrolysis products was analyzed by the normalization method of peak area. Basedon the identified pyrolysis products, the basis for tobacco flavoring tests was provided.4. The parts of synthesized compounds were applied in cigarette, and the effects on cigarettequality characteristics of adding different concentration were discussed in terms of aromacharacteristics, smoke characteristics and taste characteristics. The result indicated that adding the suitable amount of pyrazine derivatives could improve aroma quality, supplement smoking of thecigarette, and make fuller aroma, coordination. It could also reduce the mixed gas and irritation,improve the level of cigarette delicate soft, reduce dryness, clean aftertaste, and improve thesmoking quality of cigarette.