title: Self-organization of 2-acylaminopyridines in the solid state and in solution.
abstract: Aggregation of 2-acylaminopyridines and their 6-methyl derivatives in chloroform solution was studied by (1)H, (13)C, and (15)N NMR spectroscopies. The results were compared with (13)C and (15)N CPMAS NMR and IR spectral as well as with X-ray structural data. Intermolecular interactions in solution and in solid state were found to have a similar nature. Relatively strong N(amide)-H···N(pyridine) intermolecular hydrogen bonds enable dimerization to take place. Steric interactions in N-pivaloyl- and N-1-adamantylcarbonyl as well as that caused by the 6-methyl group hinder formation of the dimeric aggregates stabilized by the N(amide)-H···N(pyridine) intermolecular hydrogen bonds. In general, the DFT optimized geometries of the aggregates in chloroform solution are in agreement with the X-ray crystal structures. Wavenumbers of the stretching vibration band of the C═O group were also found indicative of the type of hydrogen bond present in the solid state.
authors.affiliation: Faculty of Chemical Technology and Engineering, University of Technology and Life Sciences, Seminaryjna 3, PL-85-326 Bydgoszcz, Poland. borys.osmialowski@utp.edu.pl
authors.forename: Borys
authors.initials: B
authors.lastname: Ośmiałowski
authors.forename: Erkki
authors.initials: E
authors.lastname: Kolehmainen
authors.forename: Robert
authors.initials: R
authors.lastname: Dobosz
authors.forename: Ryszard
authors.initials: R
authors.lastname: Gawinecki
authors.forename: Reijo
authors.initials: R
authors.lastname: Kauppinen
authors.forename: Arto
authors.initials: A
authors.lastname: Valkonen
authors.forename: Juha
authors.initials: J
authors.lastname: Koivukorpi
authors.forename: Kari
authors.initials: K
authors.lastname: Rissanen
mesh_terms: D000631:Aminopyridines / Q000737:chemistry*; D002725:Chloroform / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D015394:Molecular Structure; D012996:Solutions
chemical_list: D000631:Aminopyridines; D012996:Solutions; D002725:Chloroform