SYNTHESIS OF ANHYDRODIDEOXYHEXITOLS RELATED TO ANHYDRODEOXYHEXITOLS FROM OXO REACTION OF 3,4-DI-O-ACETYL-D-XYLAL

2,3-Di-O-acetyl-1,5-anhydro-4,6-dideoxy- D -arabino-hexitol (VI) and 2,3-di-O-acetyl-1,5-an-hydro-4,6-dideoxy- L -xylo-hexitol (VII) were prepared by reaction of methyl magnesium bromide with 3,4-di-O-acetyl- D -xylo-pyranosyl chloride. An independent synthesis of compounds (VI) and (VII) was also achieved from the 6-O-tosyl derivatives of the oxo products from 3,4-di-O-acetyl- D -xylal, thus confirming that the configuration of the secondary hydroxyls of glycals is not inverted during the oxo reaction.