On the Transfer of Chirality, Thermodynamic Stability, and Folding Characteristics of Stereoisomeric Gated Baskets

We have prepared and characterized chiral and gated baskets ( P / M )‐ 2 , each containing a twisted P or M platform and three amidopyridine gates at the rim. Racemic ( P / M )‐ 2 was found ( 1 H NMR and IR spectroscopy) to stay monomeric in CDCl 3 at 298.0 K with the gates forming a seam of intramolecular N–H ··· N hydrogen bonds. In particular, the amidopyridine gates assume a unidirectional orientation, as directed by the twisted platform, that is, the P ‐shaped cup sets the amidopyridine gates in a counterclockwise (–) orientation of intramolecular N–H ··· N hydrogen bonds (VT 1 H/ 13 C NMR and M06‐2X/6‐31G*). The folded form of spacious (355 Å 3 ) and chiral ( P / M )‐ 2 undergoes an unfolding process in the presence of the polar [D 6 ]DMSO solvent; specifically, with around 25 vol.‐% of [D 6 ]DMSO, the N–H ··· N hydrogen bonds at the rim are broken, thereby allowing a stochastic rotation of the amidopyridine gates about the rim. Interestingly, the thermal stability of folded ( P / M )‐ 2 is good with only a small fraction of unfolded state(s) forming at 104 °C in o ‐xylene.