Rearrangements During Synthetic Studies on Carba-Sugars

Rearrangements During Synthetic Studies on Carba-Sugars 

Another unexpected rearrangement was encountered in the synthesis of 1 - e/u -valiolamine, when the alkene 4 was subjected to dihydroxylation conditions. Thus, heating of a mixture of 4 with a catalytic amount of OSO4 in a water/pyridine/t-butanol mixture containing trimethylamine N-oxide under reflux for 2 days gave a mixture of 5 (29%) and the a-diol 6 (14%) together with 46% of unchanged alkene 4. 

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