A Novel Method for Synthesis of Chiral Polymer Useful for Membrane Application

Abstract

A Chiral polymer from 1,2-bis(2-methyl-1-triethylsiloxy-1-propenyloxy)ethane and dialdehyde from adipoyl chloride and 4-hydroxy benzaldehyde has been prepared in gram scale level and characterized by IR, NMR, TGA, DSC, optical rotation and Circular dichrosm (CD) study. The same was used for preparation of enantioselective membrane by phase inversion technique and the membrane was characterized for pore size and surface morphology through SEM (Scanning Electron Microscope) analysis. The enantioselective property of the membrane in the resolution of racemic compounds was studied using aqueous solution of Atenolol, Captopril, Propranolol hydrochloride and Salbutamol as feed solution. Pressure driven membrane processes were studied under pressure 4:84 Â 10 À2 N/m 2 , 24:22 Â 10 À2 N/m 2 and 48:44 Â 10 À2 N/m 2 . The Effect of feed concentration and operating pressure on membrane performance were studied differently. Solution diffusion model have been used to explain the permeation behaviour of the membrane. From this type of membrane 95% ee and 6.4 mg/m 2 h of flux were obtained.KEY WORDS: Atenolol / Captopril / Propranolol Hydrochloride / Salbutamol / Enantioselective Membrane / Chiral polymers are important in various applications, including the separation of racemic compounds and polymeric catalysis in asymmetric synthesis.1 Although various methods have been developed to synthesize chiral polymers, we focus on repetitive asymmetric reaction between prochiral monomers using a chiral catalyst. Asymmetric polymerization by means of repetitive asymmetric C-C bond forming reactions in the presence of a chiral catalyst gives optically active polymers having main chain configurational chirality. Novel optically active polymers have been prepared by asymmetric polymerization methods based on asymmetric reactions, such as asymmetric Diels-Alder reaction, asymmetric addition of allylsilane to aldehyde and asymmetric Mukaiyama aldol reaction.1 These asymmetric reactions are used for chiral polymer synthesis by repetitive asymmetric reaction between prochiral monomers to give optically active polymers. Recent progress in the method of asymmetric synthesis prompted us to design new chiral polymers by repetitive asymmetric reaction. This type of polymerization is attracting attention as one of the efficient methods for accessing optically active polymers.The Mukaiyama aldol reaction is an important C-C bond forming reaction. Based on this reaction, a number of complicated molecules, including naturally occurring compounds have been skillfully synthesized. In polymer synthesis, this type of reaction has been used as a new polymerization method called 'aldol group transfer polymerization' (aldol-GTP). All of the dialdehyde monomer used in asymmetric polymerization are useful for the aldol polymerization. Various catalytic asymmetric Mukaiyama aldol reactions of silyl enol ethers and aldehydes have been studied using chiral catalyst.

Carbon nanomaterials for designing next-generation membranes and their emerging applications

“…Based on these studies, our current focus revolves around developing CNMs-based chiral membranes, leveraging their unique properties and potential for chiral separation, which are discussed earlier. [87][88][89] The performance and success of CNM-based membranes in chiral separation can vary depending on the experimental conditions, concentration of chiral compounds, and membrane fabrication methods. Carbon materials exhibit versatile properties that can be modified to distinctive needs, offering opportunities for the development of chiral membrane separation.…”

Fabrication and application of graphene oxide modified cyclodextrin chiral separation membranes

“…Currently, the conventional chiral separation methods, including chiral chromatography, biological separation, enantioselective crystallization, are widely used in industrial production, separation and detection of chiral drugs. 2,3 However, they still have technical limitations in industrial applications, such as high energy consumption, expensive equipment and inability to operate continuously. 4 As an environmentally friendly and low consumption technology, membrane separation has been considered as one of the most promising methods in industrial separation of chiral drugs, [5][6][7] which has become a hot spot in the research of chiral drug separation.…”

Chiral Separation in Preparative Scale: A Brief Overview of Membranes as Tools for Enantiomeric Separation

“…However, sometimes it is rather difficult to make high efficient chiral separation with membranes from chiral polymers alone, when the enantiomers interact with the flexible side chains of the membrane polymers not comprising chiral sites important for the effectiveness of the molecular interactions and, consequently, enantiorecognition. Therefore, membranes were prepared using modified polymers with a chiral branch including the polymer membrane containing chiral metal-Schiff base complexes [58], polymer membranes with saccharide side chains [84], polymer membrane obtained from acetylation of beta-cyclodextrin surface-functionalized cellulose [85] or from polysulfone grafted with N-dodecyl-4(R)-hydroxy-L-proline [86].…”