Preparation of Methacrylate-Based Polymers Modified with Chiral Resorcinarenes and Their Evaluation as Sorbents in Norepinephrine Microextraction

Abstract

Aminomethylation reactions between chiral amino compounds (S)-(-)-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 (S)-(-)-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, 1H-NMR, 13C-NMR, COSY, HMQC, and HMBC techniques. The reaction of (S)-(-)-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–co–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.

Removal of Toxic Metal Ions Using Poly(BuMA–co–EDMA) Modified with C-Tetra(nonyl)calix[4]resorcinarene

“…The general scheme of the copolymer synthesis is shown in Scheme 2 . Since the composition of the reaction mixture has a great influence on the final copolymer structural characteristics, the optimal values of several parameters concerning the polymerization reaction, such as the amounts of EDMA and BuMA and the cyclohexanol ratio, were checked [ 32 , 33 ].…”

“…Taking into account that the two synthesis processes were very efficient, the next step consisted of impregnating the copolymer with the macrocycle. As mentioned before, the impregnation was adapted from the method previously developed by our research group [ 32 , 33 ] ( Scheme 3 ). For this, calix[4]resorcinarene ( 1 ) was dissolved in EtOH.…”

“…Continuing our research on the properties of calix[4]resorcinarenes [ 30 , 31 ] and the modification of polymeric surfaces [ 32 , 33 , 34 ], the present study analyzed the removal of lead(II), cadmium(II), and mercury(II) ions, using a copolymer of poly(BuMA– co –EDMA) modified with C -tetra(nonyl)calix[4]resorcinarene which was obtained via the impregnation method. Ion retention efficiency was assessed by examining the effects of time of contact, pH, and volume of sample on the effective sorption.…”

Copper(I)-Catalyzed Alkyne–Azide Cycloaddition (CuAAC) “Click” Reaction: A Powerful Tool for Functionalizing Polyhydroxylated Platforms

“…Calixarenes can be functionalized in the aromatic ring from the starting materials by varying the nature of the substituent group on the phenol or in the hydroxyl group, − while the reactivity of the resorcin[4]­arenes is mainly located at three points: on the hydroxyl groups, at position 2 of the hydroxyl group, and by modification through the introduction of functionalized aldehyde. ,− Functionalizing substances such as diazonium salts, − methyl sulfonates, , ammonium groups, , acylation, , formylation, , and aminomethylation, among others, , can be introduced into the hydroxylated platform by means of easily accessible reactions selectively, with good yields (Figure ). …”

Investigation of the Thermal, Kinetic, and Dielectric Properties of a Novel Methacrylate Polymer Derived from Naphthol-Containing Cinnamic Acid Derivative

“…Methacrylate polymer derivatives are a group of polymers that are derived from methacrylate monomers but have been modified or functionalized to exhibit specific properties or applications [1][2][3]. These derivatives can have a wide range of physical properties and applications, depending on the nature of the modifications.…”