Saccharide polymers, 1, Synthesis and polymerization of methyl 5‐deoxy‐2,3‐O‐iso‐propylidene‐ß‐D‐erythro‐pent‐4‐enofuranoside

Abstract

New "saccharide polymers" were synthesized. For this purpose the synthesis and the polymerization of an unsaturated sugar monomer, methyl 5-deoxy-2,3-O-isopropylidene-/3-D-erythro-pent-4-enofuranoside, briefly called "exo-ribene", is described. All polymers, homo-and co-polymers, were synthesized under free radical conditions. The structures and compositions of the soluble "saccharide polymers" were established by elemental analysis, 'H and "C NMR, and FT-IR spectroscopy. Some characteristics e.g. molecular weights and optical rotations are reported. Depending on the comonomer reactivity and under optimized chain reaction conditions, saccharide polymers with various sugar content and high molecular weights have been obtained.

Saccharide polymers, 3. Synthesis and polymerization of a 5,6-unsaturated fructofuranoid derivative

“…It can be concluded that the system (5/MAh) at given experimental condition leads to an alternating copolymer. This phenomenon was also observed with others unsaturared saccharide monomers 1,2) . Copolymerization with MI, which also has an electron-attracting double bond, led to a random copolymer, because MI can homopolymerize and the sugar content in the copolymer is 33%.…”

“…where T g (1) and T g (2) are glass transition temperatures of the two pure homopolymers, and W 1 and W 2 are the weight fractions of the two component polymer units.…”

“…+ (W 1 P 12 + W 2 P 21 )/T g (12) The probabilities are determined as follow: where T g (1) and T g (2) are glass transition temperatures of the two homopolymers, W 1 and W 2 are the weight fractions of the two monomers (M 1 , M 2 ), T g (12) is an experimental glass transition temperature determined from Fig. 3 at a polymer composition of 50 mol-% which can be evaluated at 150 8C.…”

“…The corresponding saccharide polymers were isolated as white powder and well characterized. Polymer compositions were determined by elemental analysis (C, H, N) and 1 H and 13 C NMR. Polymerization parameters were determined for the binary system 1,2,3,4-tetra-O-benzoyl-6-deoxy-a-D-threo-5-enohexofuranose-2-uloside (5)/MA giving the reactivity ratios r 1 = 0.47 for 5 and r 2 = 1.13 for MA.…”

“…For this approach several well-defined unsaturated sugar monomers have been prepared on the basis of monosaccharides such as D-ribose 1) , D-glucose 2) and Dfructose 3) .The polymerizable group can be exo-or endocyclic involving several positions of the sugar ring. Other examples have also been reported in which the polymerizable double bond involved the anomeric center 4,5) .…”