Synthesis of 1,2,3-triazole bridged isoidide derivatives oxime polyurethanes

Polyurethanes (PU), which are produced by the reaction of diols and isocyanates, are being used in wide range such as automotive, biomedicals, textiles, insulation material. Although, PUs are being produced from mainly petrochemicals, in recent years scientist are focused on to find out alternative/renewable materials in PUs production- such as carbohydrates, fatty acids, amino acids. In this thesis project, firstly ditosylate ester of 1,4;3,6-dianydro-2,5-di-O-tosyl-D-mannitol (3) was synthesized from 1,4;3,6-dianhydro-D-mannitol (1), which is carbohydrate and renewable diol source, and tosyl chloride. Then compound 3 was reacted with sodium azide via SN2 mechanism to obtain 2,5-diazido-2,5-dideoxy-1,4;3,6-dianhydro-L-iditol (4). In the next step, 1-[2′,5′-Dideoxy-1′,4′;3′,6′-dianhydro-L-iditol-2′,5′-diyl]bis[5-methyl-1H-1,2,3-triazol-1,4-diyl]} (5) was synthesized from the reaction between compound 4 and acetylacetone in the presence of K2CO3. In the final step of monomer synthesis, compound 5 was reacted with hydroxylamine and {1-[2′,5′-dideoxy-1′,4′;3′,6′-dianhydro-L-iditol-2′,5′-diyl]bis[5-methyl-1H-1,2,3-triazol-1,4-diyl]dietanone dioxime (6) was obtained. Structural elucidation of compound 6 was performed by spectroscopic techniques such as FTIR, NMR, LC-ESI-MS. To synthesize two-components polymers (PU-1 and PU-2), compound 6 was reacted with 1,6-hexamethylenediisocynate and 1,4-phenylenediisocyanete. Besides, compound 6 was reacted with isomannitol in different mole ratio to obtained three-components polymers (PU-3, PU-4, PU-5, PU-7, PU-8, PU-9 and PU-10). The structural elucidation of all synthesized PUs was performed by FTIR and NMR. In addition to this, the physical properties (such as TGA, DSC, GPC and SEM) of synthesized polyurethanes were also done.