Versatile functionalization and grafting of poly(ε-caprolactone) by Michael-type addition

Abstract

The Michael-type addition of aliphatic (co)polyesters onto gamma-acryloyloxy epsilon-caprolactone units is a very straightforward technique of functionalization and grafting, which is tolerant to a variety of functional groups and does not require intermediate protection/deprotection steps.

Synthesis of Functional Polymers by Post‐Polymerization Modification

“…JØrôme and co-workers have studied Michael-type addition post-polymerization modification of acrylate-functionalized polyesters. [46,47] Aliphatic copolyesters containing g-acryloyloxy-e-caprolactone units were modified with various functional groups by addition of 10 equivalents thiol reagent and 15 equivalents pyridine (catalyst) in THF (Scheme 4). [47] Conversions of 65-70 % were achieved without compromising backbone integrity.…”

“…[46,47] Aliphatic copolyesters containing g-acryloyloxy-e-caprolactone units were modified with various functional groups by addition of 10 equivalents thiol reagent and 15 equivalents pyridine (catalyst) in THF (Scheme 4). [47] Conversions of 65-70 % were achieved without compromising backbone integrity. Although polyesters with acrylate side-chain functionalities can be prepared by ROP, [46] functional groups that can act as Michael acceptors are generally incompatible with radical and ionic polymerization methods.…”

“…Michael-type addition of thiols to polyesters containing g-acryloyloxy-e-caprolactone groups. [47] Scheme 5. Radical thiol addition to poly(1,2-butadiene).…”

Recent Advances in the Functionalization of Aliphatic Polyesters by Ring-Opening Polymerization

“…Recently, thiols were added onto pendant acrylate groups of PCL. [44] For example, thiol end-capped PEO was added onto the pendant acrylic groups of PCL (content of acrylic units = 18 mol%) in the presence of pyridine (THF, room temperature, 300 h [pyridine]/[thiol]/[acrylate] = 15/10/1). The poly(CLg-EO) graft copolymer was formed as result of 65% conversion of the acrylic units.…”

PCL‐Isocyanate: A New, Degradable Macromolecular Synthon for the Synthesis of Polymeric Bioconjugates

“…In a first approach, e-caprolactone (e-CL) was polymerized with numerous heterocyclic monomers, like lactides, glycolides, and butyrolactones, as described by our group, [1][2][3] or with substituted e-CL. [4][5][6][7][8] A second approach to modulate the PCL properties is to make a chemical modification to the PCL backbone. A few years ago, we introduced a general method to chemically modify aliphatic polyester chains by activation of PCL on a polycarbanionic form.…”