Polymerization of Anhydro Sugar Derivatives. III. 1,6-Anhydro-β-D-galactopyranose and Its 2-O-Methyl Ether

Synthesis of Hyperbranched Carbohydrate Polymers by Ring‐Opening Multibranching Polymerization of Anhydro Sugar

“…Previously, Schuerch et al and other groups reported pioneering research on highly branched polysaccharides prepared by the acid-catalyzed ring-opening polymerization of the 1,6-anhydro-b-Dhexopyranose, [33][34][35][36][37][38][39][40] although the branching structure was insufficiently characterized as well as the solution properties. In other research on hyperbranched polysaccharides, Kadokawa et al [41,42] reported the synthesis of a hyperbranched polyaminosaccharide by the acid-catalyzed polymerization of an oxazoline sugar having two hydroxyl groups as an AB 2 -type monomer.…”

“…[33][34][35][36][37][38][39][40] This solid-phase polymerization, however, has the disadvantage of a heterogeneous initiation reaction, which may lead to a broad polydispersity. In order to alleviate this problem, we chose the solution polymerization of 1,6-anhydro-b-D-hexopyranose using a thermally induced cationic initiator, as shown in Scheme 1.…”

“…Schuerch et al and other groups reported the synthesis of highly branched polysaccharides prepared from 1,6‐anhydro‐ β ‐ D ‐hexopyranose using monochloroacetic acid 33–40. This solid‐phase polymerization, however, has the disadvantage of a heterogeneous initiation reaction, which may lead to a broad polydispersity.…”

Dehydration of Glucose to 5-(Hydroxymethyl)furfural and Anhydroglucose: Thermodynamic Insights

“…In this scheme, dehydration chemistry is important to remove some of the excess oxygen contained in the saccharides. In hexose dehydration, the products are 5-(hydroxymethyl)­furfural (HMF) and anhydroglucose, 1,6-anhydro-β- d -glucopyranose, also known as levoglucosan (LG), and 1,6-anhydro-β- d -glucofuranose (AGF). − The HMF is produced by triple dehydration of hexose, whereas anhydroglucose is formed by the single dehydration of glucose, and the triple dehydration of pentose results in furfural. , The HMF and furfural can serve as platforms for biomass-based chemical, fuel, and polymer industries, , whereas anhydroglucose could be used for making drugs, surfactants, and polymers. − …”

The stereospecificity of trimethyl levoglucosan polymerization

“…In previous papers of this series the polymerization of various 1,6anhydro sugar derivatives has been reported (1)(2)(3)(4) and the greater ease of polymerization of those 1,6-anhydro sugars having a free hydroxyl group on the 2 position has been noted (3,4). Recently Russian workers have found conditions under which trimethyl levoglucosan (1,6-anhydro-2,3,4-trimethyl-P-D-glucopyranose) will polymerize to products of qsp/C = 0.22 to 0.30 (unspecified concentration) and molecular weight by light scattering of 280,000 to 394,000.…”