Darzen's glycidic ester condensation reaction on poly(N‐vinyl pyrrolidone)

Abstract

SYNOPSISAbout 38% conversion of carbonyl groups into epoxy functions in the molecular chain of poly (N-vinyl pyrrolidone) using chloracetamide results in the decreased viscosity of the product. De-epoxidation of the epoxy groups introduced shows the most contributing factor towards decreased viscosity is epoxy function.In a previous study, we reported on the synthesis of some methyl aryloxymethacrylates, the polymers we obtained by different methods, and some characterization studies, such as an evaluation of MarkHouwink's constants, X-ray diffraction patterns of fibers, etc., performed on these polymers.' The present work shows the possibility of carrying out DarZen's glycidic ester condensation reaction across a polymeric carbonyl group. The use of Darzen's condensation reaction in the conversion of aldehydic and ketonic functions into epoxy function is well established in both aromatic and aliphatic compounds, including terpene ketones, by employing a host of condensing agents and a variety of condensing No reference in the literature is found, however, for the conversion of a polymeric carbonyl into an epoxy derivative. Also, polymers or copolymers having an epoxy linkage are made from monomers containing an epoxy group, which, in turn, is introduced into the precursor through Darzen's condensation, epichlorohydrin reaction, etc. It is, however, observed that commercial poly (N-vinyl pyrrolidone) , PVP, can undergo DarZen's glycidic ester condensation reaction under certain conditions. PVP finds extensive applications, especially as a water soluble polymer, and its condensation product from Darzen's reaction, which is soluble in water, is found to have a lower viscosity than PVP. In as much as viscosity reducers have

Synthesis of randomly aminated polyvinylpyrrolidone and its use in the preparation of hydrolyzable conjugates

“…1 H and 13 C NMR spectra were recorded using a VARIAN NMR system (500 and 125 MHz, respectively) in CDCl 3 using tetramethylsilane (TMS) as the internal standard. Gel permeation chromatography (GPC) analyses were carried out with Resipore (250 Â 4.6 mm, 3 mm nominal particle size) Polymer Laboratories columns.…”

“…Other authors have tried to modify the ring lactams of the polymer chains under harsh reaction conditions, which lead to non-controlled modication reactions. [10][11][12][13] Endchain functionalization and conjugationsimilar to PEGmay be achieved using special polymerization 14,15 techniques by using functional transfer agents or controlled polymerization approaches. Pseudo-side-chain type functionalizationsimilar to PHPMAmay be obtained by copolymerization of VP with a functional vinyl comonomer, [16][17][18] although this procedure leads to 'false' PVP functionalization.…”

Homologous Copolymerization Route to Functional and Biocompatible Polyvinylpyrrolidone

“…There have been attempts to laterally functionalize PVP by modifying the polymer, hydrolyzing the ring, or modifying it with bromine at high temperatures (method A of Figure 2 ). [14][15][16][17] However, these reactions are diffi cult to control and are greatly inconvenient as it is impossible to purify the obtained products because all the units, including those that have suffered undesired secondary reactions, are part of the common macromolecular chains. Because of the diffi culties in functionalizing PVP laterally by a controlled path, researchers have preferred to ignore polymer functionalization and carry out copolymerizations (method B of the Figure 2 ) using commercial functional monomers such as maleic anhydride, acrylic acid, and so on, mainly to obtain covalent conjugates with different biologically signifi cant molecules.…”

Epoxy Containing Poly-N-Vinylpyrrolidone

“…It has been shown [8] that it is basically possible to employ this reaction for introducing epoxy groups into poly-N-vinylpyrrolidone, when there is reaction of the carbonyl of the pyrrolidone ring. However, this was reported in a short communication, and the details of the reaction were not investigated.…”