Sorbitol 2,3,5,6-tetramethyl

Soltzberg, Goepp and Freudenberg10 proved the constitution of arlitan by a synthetic method. They obtained a liquid tetramethyl derivative of arlitan, characterized it by its boiling point, density and refractive index, and compared it with 2,3,5,6-tetramethyl-l,4-anhydro-D-sorbitol (V) synthesized by the following method. Tetramethyl-D-glucofuranose... 

VI) was hydrogenated to the corresponding sorbitol derivative (VII) in which the only groups unsubstituted were those situated at Cl and C4. Acid-catalyzed ring closure gave a product identical with the tetramethyl derivative of arlitan. 

The reactivity of achiral Ru compounds for the hydrogenation of functionalized ketones has not been extensively studied. RuCl2 P(C6H5)3 3 reduces y-keto carboxylic acid at 180 °C to the corresponding y-lactone (Eq. 2.15) [115]. Heterogeneous Ru/C catalyzes the atmospheric pressure hydrogenation of furfural in water at 25 °C [86]. Under such mild conditions, glucose is industrially converted to sorbitol (Eq. 2.16) [116]. At elevated temperature and pressure, tetramethyl-l,3-cyclobutanedione can be converted to a 98 2 diastereomer mixture of the diol (Eq. 2.17) [117]. 

The inner etherification induced in the sorbitol and D-mannitol structures during polyester formation, made a study of their inner ethers or anhydrides a matter of practical significance. A new monoanhydride of sorbitol was described (21) and designated arlitan (from the initials of the Atlas Research Laboratory). Identification as 1,4-anhydro-D-glucitol was made by comparison of its sirupy tetramethyl ether with that obtained by acid anhydrization of Irvine s 2,3,5,6-tetramethyl-D-glu-citoP by oxidation of the tetramethyl ether to dimethyl-L-threaric acid [0-dimethyl-L-((iea tartaric acid] and identification as the crystalline diamide and by its behavior on oxidation with lead tetraacetate. ... 

BPA is a known endocrine disrupting chemical (EDC), but this effect is sUght and has been known since the 1930s. This fear of EDC activity led to a total ban of BPA in polycarbonate plastic bottles intended for babies. The chemical industry was not really shaken by this ban as this use was only a tiny fiaction of the market. On the other hand, finding substances that rival the favorable properties BPA is not easy, and more significantly, not cheap. Isosorbide, which can be produced by artificial sweetener sorbitol, is a possible replaeement. A promising alternative of polycarbonate plastics is named Tritan co-polyester, and is made from dimethyl terephthalate, 1,4-cyclohexanedimethanol (CHDM), and 2,2,4,4-tetramethyl-l,3-cyclobutanediol (CBDO). However, replacing BPA in all current apphcatiorrs would be difficult, very expensive, and—most importantly—unlikely to save anyone from any harm. 

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