Starch tosylation

Deoxyfluorostarches were prepared from com starch by treatment of the tosylated (mostly at 0-6 of the o-glucosyl residues) starch precursors with KF in ethylene glycol (190°, 15 min) or by treatment of starch with hydrofluoric acid (Mc2SO, —30°, 4 h — room temp., 10 min). 

Poly(amino acids)2892 and polypeptides2893 can also be grafted onto starch. Starch was first alkylated in the presence of lithium naphthalene, and then the alkoxy derivatives were reacted with /V-carboxy anhydrides. Poly(amide amines) were produced by reacting amines with dioic acids on starch and then crosslinking with epichlorohydrin or 1,2-dichloroethane 2894 Grafting of starch with a synthetic polymer chain, for instance, polystyryl carboxylate anions prepared by an anionic polymerization, can be carried out on a blend of starch and cellulose functionalized by sulfonation, mesylation, or tosylation. In this manner, cellulose-starch graft copolymers were prepared.2895... 

Abstract Pure, well soluble p-toluenesulfwiyl (tosyl) starch samples with a DSm range... 

Synthesis of /Htoluenesulfonyl (tosyl) starch, and tosyl starch acetate... 

For a typical preparation, to a stirred solution of tosyl starch (1.0 g, DStos = 1.02) in 20 ml pyridine 0.3 g A iV-dimethylaminopyridine (DMAP) and 10 ml (106.0 mmol) acetic anhydride were added. The mixture was kept at 20°C for20 h and at 80 °C for 5 h. After cooling down to room temperature, the product was isolated by precipitation in 150 ml ethanol, filtered off, washed with ethanol and dried at 50 C under vacutun. 

Reaction of tosyl starch and tosyl starch acetate viith iodine... 

In order to guarantee an even distribution of the functional groups within the polymer chain, a homogeneous procedure for the tosylation reaction was preferred. It was already shown that homogeneous tosylation using the well-known starch solvent dimethyl sulfoxide does not yield products of sufficient degree of substitution . Therefore, we carried out the reaction in the solvent system A,iV-dimethyl acetamide (DMA)/LiCl which is usually applied for homogeneous functionalisation of cellulose. 

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