Aromatic Foldamers with Iminodicarbonyl Linkers:  Their Structures and Optical Properties

• Published in: Journal of organic chemistry Vol. 70; no. 4; pp. 1423 - 1431
• Main Authors: Masu, Hyuma, Sakai, Masaki, Kishikawa, Keiki, Yamamoto, Makoto, Yamaguchi, Kentaro, Kohmoto, Shigeo
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 18.02.2005; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Organic; Condensed benzenic and aromatic compounds; Exact sciences and technology; Organic chemistry; Physical Sciences; Preparations and properties; Science & Technology; PEPTIDE FOLDAMERS; STACKING; DESIGN; 4+4 PHOTOCYCLOADDITION; BETA-PEPTIDE; CONFORMATION; DRIVEN; CHIRALITY; SOLID-STATE; OLIGOMERS; Chemical solution; Molecular structure; NMR spectrometry; X ray diffraction; Naphthalene derivatives; Helicity; Fluorescence spectrometry; Circular dichroism; Crystalline state; Hydrogen 1; Imide; Absorption spectrometry; Chiral auxiliary; Optical properties; Carboxamide; Aromatic compound; Helical structure; Chemical synthesis; Intramolecular interaction; Folding; Crystalline structure
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo048233m

Carboxamides possessing naphthalene rings connected by multiple iminodicarbonyl linkers were synthesized. These molecules forced the naphthalene rings to be placed in the positions facing each other, and they form helical foldamers both in solution and in the crystalline state. Their folding structures were investigated by single-crystal X-ray analysis and 1H NMR spectroscopy. Their absorption and fluorescence spectra showed a red shift as the number of naphthalene moieties increased. This remarkable change is based on the intramolecular interaction between naphthalene moieties. Helicity of the foldamer can be controlled by the introduction of chiral auxiliaries at imide nitrogen atoms, which results in an observation of induced circular dichroism.