✍ Scribed by René Csuk; Brigitte I. Glänzer; Alois Fürstner; Hans Wiedmann; Viktor Formacek
No coin nor oath required. For personal study only.
During recent investigations on the scope of a new glycal synthesis*, an unusual isomerisation of 3,6-anhydro-5-deoxy-l,2-O-isopropylidene-cu-D-xylo-hex-5;enofuranose2 (1) was observed; 1 was described previously as the sole product of base-promoted eliminations of 3,6-anhydro-S-deoxy-5-iodo-1,2-O-isopropylidene-#l-L-idofuranose and 3,6-anhydro-l,2-O-isopropylidene-5-O-toluene-p-sulfonyl-~o-glucofirranose2 (4). When 1,2-O-isopropyiidene-5-Otoluene-p-sulfonyl-l,4:6,3a-rr-glucohexodialdodifuranos-cu,&6yi chloride3 (2) was treated with laminar Z&Ag-graphite l, the expected glycal 1 was found to be admixed with the
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