Chiral mono-N-substituted primary amides. I. Molecular packing modes

Abstract

Molecular packing modes of RCONHCH(CH3)Ar, in which R are alkyl and Ar are aromatic residues, were determined and analysed in terms of molecular interactions to be used for the interpretation of chiral recognition phenomena involving these amides. The cell constants of a number of the amides as well as the crystal structures of (R)-N-trifluoroacetyl-1-(1-naphthyl)ethylamine, (R)-and (RS)-N-acetyl-1-(1-naphthyl)ethylamine were determined. Various molecular interactions are analysed and it is shown that the hydrogen-bonded 5 A translation stack is particularly stable, sufficiently for the arrangement to be partially conserved in the melt.

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.…”

The physical crosslinking of polyurethane elastomers studied by X-ray investigation of model urethanes

“…The cell dimensions in this direction lie between 5.0 and 5.1 ]i which values are governed by the geometry of the amide group and the NH... 0 bridging bond. This is also found in other crystal structures with this type of bridging bond [39].…”

The crystal structure of p-nitrobenzyl ester of (+)-1,5-nitronaphthylsulfinylacetic acid

“…Csöregh and Eckstein, 1979a, b;Dupont et al, 1982;Weinstein and Leiserowitz, 1980), the bond distances and angles in the naphthalene ring are normal in the range 2 a.…”