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Carbohydrate-based macrocycles can be enantioselective catalysts in certain reactions. Previously, it was proven that the carbohydrate moiety could affect the catalytic activity of the monoaza-15-crown-5 type macrocycles derived from sugars. According to our experiments so far, the most effective enantioselective catalysts were the <span style="font-variant: small-caps;">d</span>-glucose- and the <span style="font-variant: small-caps;">d</span>-galactose-based crown ethers. To obtain more information about the effect of the carbohydrate unit, a rare monosaccharide, <span style="font-variant: small-caps;">d</span>-idose was incorporated into the monoaza-15-crown-5 structure. The key intermediates were methyl 4,6-<i>O</i>-benzylidene-α-<span style="font-variant: small-caps;">d</span>-idopyranoside and methyl 4,6-<i>O</i>-benzylidene-β-<span style="font-variant: small-caps;">d</span>-idopyranoside, which were synthesized from <span style="font-variant: small-caps;">d</span>-galactose. The efficiency of the idopyranoside-based crown compounds synthesized was investigated in asymmetric phase transfer reactions. In liquid-liquid biphasic reactions the highest enantioselectivity was 81% ee, while in solid-liquid phase systems the highest asymmetric induction was 67% ee. It was observed that the enantiodiscrimination was strongly dependent on the configuration of the anomeric center, on the side arm of the nitrogen, and on the structure of the substrate.