Synthesis Of Undecental Glycol Acetal And The Application In Cigarette

Recent development have involved incorporating low volatility and odorless organic compounds,called flavor precursor, which under smoking conditions was pyrolyzed into one or more fragments that function to improve the taste and character of tobacco smoke.The aim of this paper is to synthesis the flavor precursor of olefine aldehyde which can be used in tobacco flavoring.Firstly, The acetalization of 10-undecenal glycol acetal was studied. Using monofactorial test and response surface methodology(RSM), The optimum reaction conditions are as follows:the mount of p-toluenesulfonic acid as catalyst was 0.42%(w/w), molar ratio of 10-undecental to glycol was 0.20:0.26, hexane as solvent, reaction time was 70.92min, its reaction yield could reach over 96.86%. the product was isolated by reduced pressure distilled, the data of MS, IR and NMR were consistent with the construction of 10-undecental glycol acetal.the application of 10-undecental glycol acetal to tobacco flavoring was investigate. the results of flavoring sensory evaluation implied that the product can transfer comfortable flower and fruit aroma towards cigarette. we also determined its advise addition was 0.15‰～0.20‰. It is not satisfying when 10-undecental glycol acetal be used as the precursor of 10-undecental and which was disagreement with the Pyro-GC-MS analysis result.Thus, in order to attain acetal can be used as precursor of its matrix olefine aldehyde, 2-undecental glycol acetal was synthesized, and the corresponding optimum reaction conditions as: 2-undecental 0.2mol, glycol 0.3mol, cyclohexane as solvent, catalysed by vitamin C, the optium reaction time was 6h, its reaction yield could reach over 77.25%. the construction of target product was illustrated by MS, IR and NMR.Finally, from the result of mainstream smoke analysis, 2-undecental glycol acetal can be used as precursor of 2-undecental in tobacco flavoring. the ratio of which transfer to mainstream smoke directly was 4.85%, and 2.17% transfrom to 2-undecental. The results of Pyro-GC-MS implied that the main pyrolyst products is 2-undecental, sensory evaluation implied that 2-undecental glycol acetal could supply tobacco fragrance, decrease stimulation, so it can improved sensory quality of cigarette remarkably, its advise addition was 0.10‰～0.15‰.