Preparation of Designer Resins via Living Free Radical Polymerization of Functional Monomers on Solid Support

Abstract

Merrifield resin is converted to a solid-supported free radical initiator by reacting with the TEMPO-Na. Heating TEMPO-methyl resin with a variety of functionalized styrene and acrylate monomers gives larger resin beads via living free radical polymerization. We have coined the term Rasta resin to describe resin beads prepared in this fashion. The process can be described as a solvent-free suspension polymerization. It is particularly well suited for preparation of resin beads from monomers which contain electrophilic groups that would be destroyed upon suspension polymerization in water. Rasta resins have a novel macromolecular architecture wherein long straight chain polymers bearing reactive functional groups emanate from the phenyl groups of a cross-linked polystyrene core. With judicious choice of co-monomers and polymerization strategy, the solvent affinity, loading capacity, and distance of functionality from the cross-linked core may be controlled giving beads with properties that are tailored to specific uses as synthesis supports and scavenging resins.

Polymer Brushes by Nitroxide‐Mediated Polymerization

“…bate, deprotonated, and then reacted with the benzyl chlorides of the resin to covalently bind TEMPO by an ether linkage. [56] The thus formed immobilized alkoxyamine was then applied for the preparation of polymer brushes. [57][58][59] To give the reader an overview of this chapter, results obtained by the TEMPO-mediated brush formation on particles are summarized in Table 1.…”

A Convenient Solid Phase Synthesis of Disubstituted Guanidines

“…Importantly the a,a-dimethylbenzyl linkage is both TFA labile and also imparts stability on the isocyanate functionality giving a product with exceptional shelf life. This isocyanate moiety or any products yielding from the reaction with an isocyanate moiety can be cleanly cleaved by TFA/DCM at room temperature [21]. Having a reactive precursor to guanidine linked to the solid-phase with a traceless linker provides an advantage and convenience to the solid-phase synthesis of guanidines.…”

“…Aniline and most of its derivatives do not react with 1 even at higher temperature [21]. Hence such amines could not be introduced at the first diversity point.…”

Thick Coating and Functionalization of Organic Surfaces via ATRP in Water

“…The newly formed polymer presents a homogeneous radial distribution, as shown in the literature for TEMPO polymerization. [6,9] (ii) Alternatively, because of a deactivation (by radical coupling) or a non-activation (due to problematic diffusion of the copper complex and/or of the monomer) of the initiators in bulk, only surface groups start the polymerization and produce polymer chains with extremely high molecular weight in an outer shell. Experimental evidences for the discussion of the two hypotheses are reported in the following paragraphs.…”