The molecular packing modes and the hydrogen-bonding properties of amide:dicarboxylic acid complexes

“Total Synthesis” Supramolecular Style: Design and Hydrogen-Bond-Directed Assembly of Ternary Supermolecules

“…The “weaker” link in the tetrameric motif in 1 is the amide⋅⋅⋅amide interaction. Since many reported structures contain heteromeric amide⋅⋅⋅acid hydrogen bonds (in preference to the corresponding homomeric options),12, 18 our plan was to replace the amide⋅⋅⋅amide interaction with a more favorable heteromeric acid⋅⋅⋅amide interaction, thereby allowing the introduction of a third component in a specific manner. By offering two different carboxylic acids to the isonicotinamide molecule, we expected the stronger acid to interact preferentially with the best acceptor (the pyridine nitrogen atom) and the weaker acid to form a heteromeric motif with the remaining amide moiety (Scheme ).…”

Influence of structure on the kinetics of assembly of cyclic dipeptides into supramolecular tapes

“…a hydrogen atom on a heteroatom). [21][22][23][24][25] The geometry of the two hydrogen atoms on primary amides determines the type of structure that is formed through self-aggregation or by aggregation with a guest molecule. The orientation of these hydrogen atoms is defined as having either syn or anti geometry, depending on whether the hydrogen atom and the carbonyl group are located on the same side or the opposite side of the C-N bond (Fig.…”

Overlapping with Jack Dunitz

“…This crystal structure revealed the presence of repulsion between lone‐pair electrons of neighboring hydroxyl and carbonyl oxygens; the acid:amide cyclic H‐bonded dimer is not coplanar, as the carboxyl group is twisted by 20° out of the plane of the amide group. We then made use of acid:amide complementarity to prepare a series of amide:acid cocrystals . The lone pair‐lone pair repulsion was taken advantage of in later years in a study conducted with Meir Lahav on the growth of amides in solution in the presence of the corresponding carboxylic acid; in particular, asparagine monohydrate in the presence aspartic acid as a tailor‐made additive.…”