Synthesis and structural studies of N-(p-toluenesulfonyl)-amino acid 3,5-di-tert-butyl-2-phenolamides

This paper describes the synthesis and structural studies of N-(p-toluenesulfonyl)-amino acid 3,5-di-tert-butyl-2-phenolamides by ¹H, ¹³C, and ¹⁵N. The presence of intra- and intermolecular hydrogen bonds were studied by variable temperature NMR spectroscopy. The molecular structure of two amides in the solid state was determined by X-ray diffraction experiments. The results show that tert-butyl substituents in the phenolic ring have important effects in the nature of hydrogen bonds and conformation of these amides. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:114–120, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10223     

Structural Studies by NMR and X-Ray Crystallography of N-(p-Toluenesulfonyl)-Amino Acids

N-(p-Toluenesulfonyl)-glycine 7 and analogous derivatives of d,l-alanine 8, L-valine 9, L-leucine 10, L-isoleucine 11, and L-phenylalanine 12 were synthesized by condensation of the amino acid with p-toluenesulfonyl chloride. The presence of intermolecular hydrogen bonding was established by variable NMR spectroscopy. The molecular structure and intermolecular interactions of N-(p-toluenesulfonyl)–d,l-alanine and N-(p-toluenesulfonyl)–L-valine were corroborated by X-ray diffraction (XRD) experiments.