title: Compartmentalization of single polymer chains by stepwise intramolecular cross-linking of sequence-controlled macromolecules.
abstract: We report the intramolecular double compaction of sequence-controlled linear macromolecules into "structured" random coils. These compartmentalized single-chain objects were prepared by performing successive cross-linking reactions in an orthogonal fashion. The foldable precursors were synthesized by sequence-controlled copolymerization of styrene with N-substituted maleimides (MIs), namely pentafluorophenyl 4-maleimidobenzoate (1) and TIPS-protected N-propargyl maleimide (2). These two functional MIs allow intramolecular cross-linking. The activated ester pentafluorophenyl moieties of 1 were reacted with ethylenediamine, whereas the deprotected alkyne functions of 2 were self-reacted by Eglinton coupling. The compaction of model copolymers containing only one cross-linkable zone (i.e., either 1 or 2) was first studied. (1)H NMR and SEC analysis indicated that these structures could be efficiently compacted into single-chain objects. Thus, more complex copolymers containing two individually addressable cross-linking zones were prepared and sequentially compacted. Detailed characterization of the folding process indicated that double-compaction occurred and that the formed single-chain particles contain distinct cross-linked subdomains.
authors.affiliation: Precision Macromolecular Chemistry Group, Institut Charles Sadron, UPR-22 CNRS , BP 84047, 23 rue du Loess, 67034 Strasbourg Cedex 2, France.
authors.forename: Raj Kumar
authors.initials: RK
authors.lastname: Roy
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Lutz
mesh_terms: D000480:Alkynes / Q000737:chemistry; D003432:Cross-Linking Reagents / Q000737:chemistry*; D008301:Maleimides / Q000737:chemistry; D008958:Models, Molecular; D009019:Morphinans / Q000737:chemistry; D058105:Polymerization; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry*; D020058:Styrene / Q000737:chemistry
chemical_list: D000480:Alkynes; D003432:Cross-Linking Reagents; D008301:Maleimides; D009019:Morphinans; C440369:N-propargyl; D011108:Polymers; C043592:maleimide; D020058:Styrene