Geraint Jones

TL;DR: The crystal structures reveal that 18-crown-6 adopts an all-gauche conformation with pseudo D3d symmetry in which the intermolecular N −H ⋯ O hydrogen-bonding interactions between the macrocyclic polyether and the adducts are associated directly with the triangle of oxygen atoms on the complexing face of the crown as discussed by the authors.

TL;DR: In this paper, an X-ray crystal structure determination of the 1:1 complex formed between NN′-dimethyl-1,7-diaza-4,10-dioxacyclododecane (1) and benzylammonium thiocyanate and dynamic 13C n.m.r.

TL;DR: A chiral 30-crown-10 derivative of D-mannitol, DD-(2), has been shown by X-ray crystallography and dynamic 13C n.m.r. spectroscopy to adopt, in both the solid state and in solution, a "face-to-back" conformation which must undergo substantial change in order to create the hydrophilic cavity necessary for the formation of complexes with Li+, Na+, K+, Rb+, NH4+, MeNH3+, and ButNH3+ ions as mentioned in this paper.

TL;DR: X-ray crystallography has revealed that the chiral 30crown-10 derivative DD-(2) adopts a basket-like conformation when it forms a 1 : 1 :1 complex with (S)-[PhCHMeNH3]+ CIO4+ and H2O in the solid state; 1H n.m.r. spectroscopy suggests that 1:1:1 complexes of this type between (i)DD-(2), R1NH3+ cations, and H 2O, and (ii)DD-, R1 NH3+