Study On Synthesizes Of N-methyl Pyrrole Derivatives And Application In Cigarette

This Paper studied the Synthesis of 12 pyrrole derivatives by Paal-Knorr, esterification reactions, respectively. The optiziming condition of Paal-Knorr reaction and esterification reactions were disscussed. The structures of target compounds were confirmed by IR, ¹H NMR, ¹³C NMR, HRMS, TG-DTG-DSC. The pyrolysis and tobacco flavoring of compounds were researched. The all study results as follows:1. Acetonylacetone was treated with amino acid (Valine, leucine) to give two 2,5-dimethyl-N-substitute derivatives by Paal-Knorr reaction.2. Using the new N-pyrrole glycin, N-pyrrole valine and N-pyrrole leucine compounds as materials, esteracated with seven spice alcohols (isoamyl alcohol, menthol, rhodinol, octyl alcohol, Nonenol, geraniol, anisyl alcohol), then one N-(2, 5-dimethyl pyrrole) valine esters and seven N-(2,5-dimethyl pyrrole) leucine esters were obtained via esterification reaction, eight new compounds were obtained in all. The reaction effect of different catalytic, solvent, temperature was compared. The optimal synthesis condition was determined: under room tempertature, DCC as condensing agent, DMAP as catalytic, acetonitrile as solvent, the highest yield was obtained.3. Acetyl acetone as raw material, bromine as coupling agent, THF as solvent were coupled to give a symmetrical diketone: 3,4-diacetyl-2,5-hexanedione, then use the diketone as material to compare the Paal-knorr reaction in different condition with thiocarbamate, amino thiourea, glycine and o-phenylenediamine, The optimal synthesis condition was determined: thiourea, amino thiourea and o-phenylenediamine with anhydrous alcohol + glacial acetic acid, the fastest reaction time and in the highest yield; glycine with anhydrous alcohol + glacial acetic acid as a solvent, in addition to join 0.15 g p-toluene sulfonic acid as catalyst, can get the best yield and the fastest response time. This route get four new compounds altogether.4. Simultaneously the thermolysis of N-(2,5-dimethyl) pyrrole glycin ester was studied at 300°C,600°C and 900°C, respectively. Pyrolysis mechanism was discussed. The comparison and analysis of 65, 55, 85 and 56 kinds of thermolytic products indicated that various aromas would be produced and improve the tobacco's taste and flavor.5. The compounds were applied in cigarette, the result indicated that adding the suitable amount of pyrrole derivetavies could efficiently improve smoking quality of the cigarettes, increase quantity of tobacco aroma, reduce offensive odor and irritation, amend aftertaste, the rational consumption was 0.02%.