1,4:3,6-Dianhydrohexitols esters

Circular dichroism of the nitrato (ONO) chromophore of the mono- and di-nitric esters of l,4 3,6-dianhydrohexitols was found to consist of two dichroic bands, one weak and positive, at about 265 nm, and a stronger band at —228 nm, which was positive for the endo-(R)-nitrato chromophore and negative for the exo-(S)-nitrato group.68 However, for l,4 3,6-dianhydro-D-glucitol dinitrate, which has both an endo and an exo nitrato group, both bands were positive, but [ ]ma r (+ 7,260) for the band at 225 nm was about half of the algebraic sum of this band for the di-endo (+ 18,400) and di-exo (—4,460) compounds. 

The exception noted for hydroxyl ions in rule (2) is well established for other sulfonic esters of carbohydrates, which therefore differ from simple alkyl sulfonates. An example of hydrolysis of an exo sulfonyloxy group is provided by the compound described as methanesulfonyl-monochloro-l,4 3,6-dianhydrosorbitol which must now be designated 1,4 3,6-dianhydro-5-chloro-5-deoxy-2-0-mesyl-L-iditol reaction with sodium hydroxide affords the free, hydroxy compound of the same configuration. Examples of the hydrolysis of endo sulfonyloxy groups are not available in the dianhydrohexitols, but the endo tosyloxy group in the stereochemically equivalent 3,6-anhydro-l, 2-0-isopropylidene-5-0-tosyl-D-glucofuranose (LXVII) is hydrolyzed by sodium hydroxide to the corresponding hydroxyl... 

The p-toluenesulfonic ester 14 is an example of an exo-sulfonate in a cts-fused, five-membered ring-system, a system which also occurs in some dianhydrohexitols. Although they did not identify the products, Matheson and Angyal183 compared the reactivity of the three l,4 3,6-dianyhdro-2,5-di-0-p-tolylsulfonylhexitols 18, 19, and 20... 

Storbeck and Ballauff were the first to report on polyesters based on FDCA and dianhydro-hexitols [16]. Here, the acid chloride of FDCA was reacted with all three dianhydrohexitol isomers, in 1,1,2,2-tetrachloroethane in the presence of pyridine, giving white, fibrous polyesters. This work has been discussed in detail in the preceding section on isohexide polyesters (section 9.2.2). Later, Gandini and co-workers performed some kinetic studies on the transesterification of the FDCA dimethyl ester [66-68]. However, little attention was paid to polymer properties. More recently a series of papers on FDCA polyesters has been published by various groups, indicating the renewed interest in this subject. 

In addition, isosorbide and other l,4 3,6-dianhydrohexitols (isomannide derived from D-mannose, isoidide derived from L-fructose) are also attractive to serve as monomers for polymer production due to their rigidity, chirality, and non-toxicity (Fig. 6). Such features may introduce special properties into the polymers formed, such as enhanced Jg and/or special optical properties. Their innocuous nature also opens the possibility of applications in packaging or medical devices. As a bifunctional monomer, isosorbide can be polymerized with other bifunctional monomers via condensation polymerization. A recent review described various isosorbide-based polymers synthesized, including polyesters, polyamides, poly(ester amide)s, poly(ester imide)s, polycarbonates, polyurethanes, and so on [308], and the present... 

Synthetic drying oils from D-glucitol and D-mannitol, and drying oil acids have been described 104), Dianhydrohexitols completely esterified with saturated, medium-length fatty acids are useful as plasticizers 105). Analogous esterification products have been obtained from the reaction of hexitols with rosin drying oil acids, phthalic anhydride, and succinic and citric acids. The diacrylate and dimethacrylate esters of the dianhydrohexitols polymerize readily on being heated 106). 

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