Progress and challenges in the synthesis of sequence controlled polysaccharides

• Giulio Fittolani,
• Theodore Tyrikos-Ergas,
• Denisa Vargová,
• Manishkumar A. Chaube and
• Martina Delbianco

Beilstein J. Org. Chem. 2021, 17, 1981–2025, doi:10.3762/bjoc.17.129

• glycosidic bond formation. Control over the polysaccharide length (degree of polymerization, DP) and regioselective insertion of modifications or branches are additional challenges. Three main approaches are available (Figure 1): A) enzymatic polymerization [10][11][12][13][14][15][16][17], B) chemical

• of the self-assembly of cellulose chains at the active site of the enzyme suggested that diffusion of the aggregated molecules and the monomers around the active center dictates the DP that can be obtained by enzymatic polymerization [70][71]. This could be the reason causing enzymatic reactions to

• observed for cellulose [67][79], while the multifluorinated compound formed considerably shorter platelets. Cellulose–xylan [80] and cellulose–chitin [81] hybrids were also obtained upon enzymatic polymerization of the respective dimers. An amino or azido functionality in the C-6 position allows for

Nanoreactors for green catalysis

• M. Teresa De Martino,
• Loai K. E. A. Abdelmohsen,
• Floris P. J. T. Rutjes and
• Jan C. M. van Hest

Beilstein J. Org. Chem. 2018, 14, 716–733, doi:10.3762/bjoc.14.61

• recycling. Polymeric nanoreactors were also used to perform ring-opening polymerization (ROP) in water. Nallani et al. reported on the enzymatic polymerization of lactones using CalB, which was immobilized in both the polymersome lumen and bi-layer [21]. Nanoreactors for ROP were prepared from polystyrene

• encapsulated in the lumen of the polymersome Pickering emulsion (right). Adapted with permission from [79]. Cross-linked polymersomes with Cu(OTf)2 catalyst. Reprinted with permission from [15]. Schematic representation of enzymatic polymerization in polymersomes. (A) CALB in the aqueous compartment (B) CALB

New enzymatically polymerized copolymers from 4-tert-butylphenol and 4-ferrocenylphenol and their modification and inclusion complexes with β-cyclodextrin

• Adam Mondrzyk,
• Beate Mondrzik,
• Sabrina Gingter and
• Helmut Ritter

Beilstein J. Org. Chem. 2012, 8, 2118–2123, doi:10.3762/bjoc.8.238

• (N3-β-CD) was carried out. The formation of inter- and intramolecular inclusion complexes was investigated by DLS measurement. Keywords: copolymer; ß-cyclodextrin; enzymatic polymerization; 4-ferrocenylphenol; polyphenol; 4-tert-butylphenol; horseradish peroxidase; HRP oxidative coupling; inclusion

Miniemulsion polymerization as a versatile tool for the synthesis of functionalized polymers

• Daniel Crespy and
• Katharina Landfester

Beilstein J. Org. Chem. 2010, 6, 1132–1148, doi:10.3762/bjoc.6.130

• obtained. The synthesis strategy paved the way for various water-free reactions to be performed in the miniemulsion nanodroplets, including the formation of hydrophilic polyurethane capsules and particles as discussed below. Enzymatic polymerization Enzymatic polymerization could be successfully performed

• in direct miniemulsion with significant advantages compared to the traditional bulk process. In fact, the bulk process yields only low molecular weight polymers and conversions are limited to 80% after 5 days (see Figure 5). Polyesters were polymerized by enzymatic polymerization of pentadecanolide