Nitriles, Dithioacetals, and Methyl Ethers

Williams and J. K. N. Jones have shown that the dithioacetals of aldopentoses and aldohexoses may be separated as their acetates.472 In certain cases, however, isomers were not separated (for example, D-altrose and D-talose), but reduction of the dithioacetal to the 1-de-oxyalditol permitted resolution of the acetates. The method is not suitable for quantitative determinations, but it does preserve the 

The separation of fully methylated alditols has been investigated by Ovodov and Evtushenko,231 but is not suitable for routine use, because of the time necessary for the preparation of such derivatives, and the lack of resolution. 

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