Castillo-Aguirre Alver, Maldonado Mauricio
Departamento de Química, Facultad de Ciencias, Universidad Nacional de Colombia-Sede Bogotá, 30 No. 45, Carrera 03, Colombia.
Polymers (Basel). 2019 Aug 30;11(9):1428. doi: 10.3390/polym11091428.
Aminomethylation reactions between chiral amino compounds ()-(-)-1-phenylethylamine and l-proline with tetranonylresorcinarene and tetra-(4-hydroxyphenyl)resorcinarene in presence of formaldehyde were studied. The reaction between l-proline and resorcinarenes generated regioselectively chiral tetra-Mannich bases, due to the molecular incorporation of the fragment of the chiral amino acid. On the other hand, tetranonylresorcinarene and ()-(-)-1-phenylethylamine formed regio- and diasteroselectively chiral tetrabenzoxazines, both by chiral auxiliary functionalization and by the transformation of the molecular structure that confers inherent chirality. The products obtained were characterized using IR, H-NMR, C-NMR, COSY, HMQC, and HMBC techniques. The reaction of ()-(-)-1-phenylethylamine with tetra-(4-hydroxyphenyl)resorcinarene did not proceed under the experimental conditions. Once the chiral aminomethylated tetra-(4-hydroxyphenyl)resorcinarene was obtained, the chemical modification of poly(GMA--EDMA) was studied, and the results showed an efficient incorporation of the aminomethylated compound. For the physical modification, chiral aminomethylated tetranonylresorcinarenes were employed, finding that the incorporation of modified resorcinarenes occurs, but with less efficiency than that observed using chemical modification. The modified polymers were characterized via FT-IR, scanning electron microscopy imaging, and elemental analysis. Finally, polymers modified with chiral resorcinarenes were used as sorbents in norepinephrine microextraction; for practical purposes, artificial urine was prepared and used. To perform the microextraction, the decision was made to use the modern rotating-disk sorptive extraction technique (RDSE), because of its analytical attributes as a green, or eco-friendly, technique. According to the results, the method preliminarily validated for the determination of norepinephrine in artificial urine shows that the modified polymer with chiral derivative of tetra-(4-hydroxyphenyl)resorcinarene worked effectively as a new sorbent phase for the quantitative microextraction of norepinephrine, exhibiting high stability and homogeneity of composition and structure within the working range.
研究了手性氨基化合物（）-（-）-1-苯乙胺和L-脯氨酸与四壬基间苯二酚芳烃和四（4-羟基苯基）间苯二酚芳烃在甲醛存在下的氨甲基化反应。由于手性氨基酸片段的分子掺入，L-脯氨酸与间苯二酚芳烃之间的反应区域选择性地生成了手性四曼尼希碱。另一方面，四壬基间苯二酚芳烃和（）-（-）-1-苯乙胺通过手性辅助官能化以及通过赋予固有手性的分子结构转变，区域和非对映选择性地形成了手性四苯并恶嗪。使用红外光谱、氢核磁共振、碳核磁共振、化学位移相关谱、异核多量子相干谱和异核多键相关谱技术对所得产物进行了表征。在实验条件下，（）-（-）-1-苯乙胺与四（4-羟基苯基）间苯二酚芳烃的反应未进行。一旦获得手性氨甲基化的四（4-羟基苯基）间苯二酚芳烃，就研究了聚（甲基丙烯酸缩水甘油酯-二乙烯基苯）的化学改性，结果表明氨甲基化化合物有效掺入。对于物理改性，使用了手性氨甲基化的四壬基间苯二酚芳烃，发现改性间苯二酚芳烃发生了掺入，但效率低于化学改性。通过傅里叶变换红外光谱、扫描电子显微镜成像和元素分析对改性聚合物进行了表征。最后，用手性间苯二酚芳烃改性的聚合物用作去甲肾上腺素微萃取的吸附剂；出于实际目的，制备并使用了人工尿液。为了进行微萃取，决定使用现代旋转盘吸附萃取技术（RDSE），因为它作为一种绿色或环保技术具有分析特性。根据结果，初步验证用于测定人工尿液中去甲肾上腺素的方法表明，用四（4-羟基苯基）间苯二酚芳烃的手性衍生物改性的聚合物有效地作为一种新的吸附剂相用于去甲肾上腺素的定量微萃取，在工作范围内表现出高稳定性以及组成和结构的均匀性。
