Summary: | Dulcitol hexanitrate was prepared in 90% yield by nitrating dulcitol with nitric and sulphuric acid. The optically inactive hexanitrate crystallized from ethanol and water to give fine, colorless needles melting at 98-99°C.
When the pure dulcitol hexanitrate was dissolved in anhydrous pyridine, an exothermic reaction occurred with the evolution of a gas. On dilution of the solution with water, a crystalline dulcitol pentanitrate separated in 65% yield. The pentanitrate was re-crystallized from ethanol and water as fine, colorless needles, which melted at 85-86°C; it was optically inactive and did not reduce Fehling's solution.
The pentanitrate was methylated with silver oxide and methyl iodide, and then reduced with hydrogen over palladized charcoal to give an optically inactive monomethyl dulcitol. This product crystallized from ethanol as heavy, colorless crystals which melted at 149-150°C.
Periodate oxidation of the monomethyl dulcitol indicated that it was a racemic mixture of 3- and 4-methyl D-dulcitol (D-galactitol). Hence the action of pyridine selectively removed a nitric acid ester group from the 3-(or chemically equivalent 4-) position in the D-dulcitol hexanitrate molecule leaving a hydroxyl group. === Science, Faculty of === Chemistry, Department of === Graduate
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