[NH ... N]+ Hydrogen Bonds in Crystalline Salts of Monoaza- and Diaza-bicyclo[2.2.2]octane
نویسندگان
چکیده
IR and Raman spectra and phase transitions have been studied on various salts of azabicyclo[2.2.2]octane (ABCO) and l,4-diazabicyclo[2.2.2]octane (DABCO) which forms with simple strong acids adducts of 2 : 1, 1 : 1 and 1 : 2 composition. Only 2 : 1 DABCO adducts form homoconjugated cations containing [NH · · · H]+ hy. drogen bonds close to symmetrical ones, showing broad absorption in the low frequency region and strong temperature effect. The Evans holes observed in this case can be ascribed to a coupling of protonic vibrations with skeletal <58 (N-C3) and bas (N-C3) modes.
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