Polymerization of Unsaturated Sugars I. Radical Copolymerization of D-Glucal Derivatives and Maleic Anhydride

Abstract

ABSTRACT:Tri-0-acetyl-, tri-0-benzyl-, tri-0-methyl-o-glucal were copolymerized with maleic anhydride (MAnh) to afford novel vinyl copolymers containing sugar residues in the main chain. Tri-0-benzyl-o-glucal (TBG) showed higher copolymerization reactivity with MAnh than the other glucal derivatives. The copolymerization of TBG and MAnh was carried out at various monomer feed ratios to give the copolymers always rich in MAnh units. Both the complex and penultimate models could explain the compositional data, but the analysis of the copolymerization rate suggested the participation of the CT complex in the propagation.

Polymerization of Unsaturated Sugars II. Radical Copolymerization of a Furanoid Glucal, 3-O-Benzyl-1,2-dideoxy-5,6-O-isopropylidene-d-arabino-hex-1-enofuranose

“…After purification by column chromatography, it was dissolved in 326 ml of dimethylformamide and treated with 10.5 g of a 55% NaH oil suspension (0.24 mol) and 30.4 g (0.24 mol) of benzyl chloride as described for the preparation of 3,4,6-tri-O-benzyl-o-glucal. 7 The crude product was distilled under vacuum and then chromatographed over silica gel with hexaneether (3: I in volume) to give the pure 3-Obenzylated product (BIF) as a colorless liquid; Rf=0. 44 …”

“…They were, however, higher than those of the copolymers derived from pyranoid glucals. 7 This may be interpreted in terms of the relatively lower steric hindrance of the fivemembered ring structure of BIF than the sixmembered ones.…”

“…For the analysis of the copolymerization of a pyranoid glucal and MAnh, the complex model was shown to be more appropriate than the penultimate model, 7 and thus the complex model was applied for the copolymerization of BIF and MAnh. According to the complex model analysis which considers the participation of the charge-transfer complex of donor and acceptor monomers, each propagation 1oor-----------~…”

“…5·6 In the previous paper 7 we described the radical copolymerization of pyranoid glucal derivatives with maleic anhydride, affording novel vinyl copolymers containing sugar residues in the main chain. However, the resulting copolymers had only low molecular weights presumably owing to steric hindrance at the propagation transition step.…”

Saccharide polymers, 4. Synthesis and polymerisation of 1,2-unsaturated fructopyranoid derivatives

“…By far, a variety of "vinylsaccharides", having pendent saccharide residues, and "unsaturated sugars" have been synthesised. [1][2][3][4] The free radical polymerisation of the "vinylsaccharides" afforded a variety of "poly(vinylsaccharide)s" with typical broad molecular weight distribution. [5][6][7][8][9][10][11][12][13] Recently, amphiphilic block copolymers containing well-defined "glycopolymers" as hydrophilic segments, have been synthesised by living cationic polymerisation or atom transfer radical polymerisation (ATRP) of "vinylsaccharides", catalysed with transition metal.…”