【作者】 金显春；

【导师】 王锦堂；

【作者基本信息】 南京工业大学 ， 应用化学， 2003， 硕士

【摘要】 VC又叫 抗坏血酸。是一种具有连二烯醇结构的五元环内酯，易受到光、热、氧、湿气、pH和金属离子等的影响。基于VC的易于氧化和对热不稳定，寻求稳定VC源势在必行。本论文研究了两种新型稳定VC源—VC多聚磷酸酯（AsPP）与VC棕榈酸酯（AP）的制备，并研究了VC多聚磷酸酯的稳定性。本论文采用两种不同的磷酸化试剂与维生素C反应合成了VC多聚磷酸酯。（1）采用六偏磷酸钠作为磷酸化试剂，单因素试验方法合成了VC多聚磷酸酯。（2）采用三偏磷酸钠作为磷酸化试剂，用正交法合成了VC多聚磷酸酯。该方法的最佳合成工艺条件为pH=10.00、n（L-抗坏血酸）：n（三偏磷酸钠）=1.00：1.30、反应温度为t=34℃、不使用催化剂。所得产品经IR、13C—NMR分析证明其结构与预期产物相符。AsPP在碱性条件下较在酸性条件下稳定，在pH=10.00的碳酸盐缓冲溶液中最为稳定。 采用两种方法合成了VC棕榈酸酯。（1）以L—抗坏血酸与棕榈酸为基本原料，以高浓度硫酸为催化剂，棕榈酸甲酯为中间体，利用酯交换法在L—抗坏血酸的C6—OH上酯化合成了VC棕榈酸酯。产率为84.4%。（2）以L—抗坏血酸与棕榈酸为基本原料，棕榈酰氯为中间产物，以酰氯法合成了VC棕榈酸酯。产率72.5%。产品经元素分析、IR、C—NMR分析证明其结构与预期相符。更多还原

【Abstract】 Vitamin C is also called as ascorbic acid,which is a cyclopent-ester,with a hydroxy group in each carbon atom of the carbon-carbon double bond.For its special structure,it is easily affected by light、heat、oxygen、huminity、pH and metal cations.For its easily to be oxidated,unstable to heat ,it is urgent to develop new vitamin C source.In this article we have studied two kinds of new stable vitamin Cs synthesis,they are ascorbyl polyphosphate(AsPP)and ascorbyl palmitate(AP).We have also studied the stability of ascorbyl polyphosphate. In this article,we used two kinds of phosphate agent to react with vitamin C to prepare ascorbyl polyphosphate.(1)We used sodium hexmetaphosphate as phosphate agent,using single -factor experimental method,successfully synthesized the expected product.(2)Using sodium trimetaphosphate as phosphate agent ,we used orthogal design to seek the best synthetic methodology of ascorbyl polyphosphate.When the molar ratio of L-ascorbic acid and sodium trimetaphosphate was 1.00:1.30,pH=10.00,the temperature of the solution was 34℃,with no catalyst ,we got a high yield 99.8% and with high quality.The structure of the product has been confirmed by IR and C-NMR. In this article,we used two different methods to synthesis ascorbyl palmitate.(1)ester-exchange method.First,palmitic acid was esterified and methyl palmitate was obtained.Then ascorbyl palmitate was prepared through methyl palmitate with ascorbic acid at the presence of high concentrated sulfic acid.(2)Acyl esterific method.First,palmitic acid was acylated and palmitoyl chrolide was obtained.Then ,L-ascorbyl palmitate was prepared through palmitoyl chrolide reating with L-ascorbic acid.The IR and C-NMR spectra of the product was identified.更多还原