Synthesis of a novel starch-derived AB-type polyurethane

Abstract

SUMMARY Starting from 1,4:3,6-dianhydrosorbitol (DAS, l), a five step monomer synthesis led to 2-deoxy-1,4 : 3,6-dianhydro-2-isocyanato-~-iditol, 9, which by catalytic polyaddition gave polyurethane 13. A second route required the synthesis of 2-azido-5-O-chloroformyl-2-deoxy-1,4 : 3,6-dianhydro-~-iditol, 11. During catalytic hydrogenation, the intermediate 2-aminochloroformyl derivative 12 underwent spontaneous polycondensation. The structure of 13 was characterized by 'H and I3C NMR, IR spectroscopy and elemental analyses. Gel-permeation chromatography showed &?" = 8000-12000 corresponding to a degree of polymerisation up to 70. Differential scanning calorimetry revealed the polyadduct to be semicrystalline with a glass transition at Tg = 118°C and a melting range of 190-200°C. The polycondensation product was found to be crystalline with a melting range of 140-180°C.

Synthetic Polymers from Sugar-Based Monomers

“…175 The polymerization can be catalyzed by a metal catalyst, the most widely used being dibutyltin dilaurate (DBTDL), 176 tetrabutyl titanate (TBT), 177 and a family of commercial tin mercaptide esters registered as Metatin. 178 Tertiary amines can also speed up this process; among them, the most extensively selected catalysts are 1,4-diazabicyclo[2.2.2]octane (DABCO) 179 and N,N-dimethylcyclohexylamine (DMCHA).…”

“…An alternative synthesis has been described through the 2-azido-5-O-chloroformyl-1,2-dideoxy-1,4:3,6-dianhydro-L-iditol which underwent spontaneous polycondensation by catalytic hydrogenation via the 2-amino-5-O-chloroformyl isoidide. 176 Transformation of the 2,5-diamino-dianhydrohexitols 82−84 into the corresponding diisocyanates was achieved Chem. Rev.…”

Nitrogen-functionalized Isohexides in Asymmetric Induction

“…For the displacement of endo-tosylated molecules, compounds 18 or 19 (or their phenylsulfonate analogue [34a] ) were reacted with primary alkyl amines, including benzylamine. [35a,41] Sodium azide was handled in different solvents: DMF, [42] [bmim]BF 4 , [21,35c] leading to azido derivatives with moderate to very good yields. From derivative 20a, primary alkyl amines (benzylamine, cyclohexylamine, cyclohexylmethylamine, isopropylamine, tert-butylamine) could be introduced in endo position with 56-85% yield under classical heating or microwave irradiation.…”

Partially bio-based polyimides from isohexide-derived diamines

“…8,10 Therefore, many chemical modifications have been explored to enhance the reactivity of isohexides, including chain extensions by nucleophilic substitution, 10 as well as the introduction of more reactive functionalities, such as amines, [21][22][23] primary hydroxyl groups, [24][25] carboxylic acids, 25-26 and isocyanates. [27][28] Polymers with reasonably high molecular weights can be easily prepared using these isohexide derivatives.…”