| Abstract
| - Four intramolecular hydrogen bonding-driven aromatic amide foldamers 2−5 have been designed andsynthesized in which a 2-methoxy-3-nitrobenzamide unit was incorporated at the end of the backbone.Kinetic studies in dioxane−water (4:1, v/v) at 60−90 °C have revealed that the folded backbone of theoligomers was, like the rigidified spherand, able to complex Li+, Na+, and K+ and, consequently,accelerated the hydrolysis of the nitro-appended anisole unit of the foldamers. Generally, longer foldamersdisplayed an increased accelerating effect, and LiOH displayed the highest reactivity probably due to themost efficient complexation by the folded oligomers. Addition of excessive potassium chloride substantiallyreduced the complexing interaction, and the hydrolysis of the longer oligomers became slower than thatof the shorter ones due to an increased steric effect. The results indicate that, even in a hot aqueousmedium of high polarity, intramolecular hydrogen bonding is still able to induce structurally matchedoligomers to generate a preorganized rigidified conformation.
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