Properties of bridgehead-substituted polycycloalkanes. Synthesis and NMR analysis of /sup 15/N-labeled 1-aminobicycloalkanes and their hydrochlorides

Journal Article · Wed Apr 29 04:00:00 EDT 1987 · J. Am. Chem. Soc.; (United States)

DOI:https://doi.org/10.1021/ja00243a030· OSTI ID:6802799

Della, E W; Kasum, B; Kirkbride, K P

NMR analysis of adamantane and four bicycloalkanes substituted at the bridgehead with /sup 15/N-labeled amino and ammonio groups is described. It is found that where most of the one-bond carbon-nitrogen coupling constants are relatively large, those in 1-aminobicyclo (1.1.1)pentane and its hydrochloride are significantly reduced; in fact, in the latter compound one-bond /sup 13/C-/sup 15/N coupling could not even be detected. Values of experimentally determined vicinal couplings were in accord with those expected on the basis of the number of three-bond pathways available for transmission of spin-spin information; INDO calculations, however, suggest that in the more highly strained systems there is a substantial contribution to /sup 3/J(CN) arising from through-space interactions and that these oppose through-bond effects. Large four-bond /sup 15/N-/sup 1/H couplings were found to occur in 1-aminobicyclo(1.1.1)pentane and its hydrochloride; MO calculations indicate that through-space interactions constitute the predominant mechanism contributing to /sup 4/J(/sup 15/N-/sup 1/H), although in this case through-bond and through-space effects reinforce each other. The nitrogen-15 chemical shifts of the amine hydrochlorides were determined, and they appear to occur in random fashion.

• Research Organization: Flinders Univ. of South Australia, Bedford Park
• OSTI ID: 6802799
• Journal Information: J. Am. Chem. Soc.; (United States), Journal Name: J. Am. Chem. Soc.; (United States) Vol. 109:9; ISSN JACSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
ALKANES
AMINES
CHEMICAL PREPARATION
CHEMICAL PROPERTIES
CHEMICAL SHIFT
CHLORIDES
CHLORINE COMPOUNDS
COUPLING CONSTANTS
CYCLOALKANES
DATA
EXPERIMENTAL DATA
HALIDES
HALOGEN COMPOUNDS
HYDROCARBONS
INFORMATION
ISOTOPES
LABELLED COMPOUNDS
LIGHT NUCLEI
MAGNETIC RESONANCE
MOLECULAR ORBITAL METHOD
NITROGEN 15
NITROGEN ISOTOPES
NMR SPECTRA
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
RESONANCE
SPECTRA
STABLE ISOTOPES
SYNTHESIS