%0 Generic
%A Kelly, Brendan
%A O'Donovan, Daniel H.
%A O'Brien, John
%A McCabe, Thomas
%A Blanco, Fernando
%A Rozas, Isabel
%D 2016
%T Pyridin-2-yl Guanidine
Derivatives: Conformational
Control Induced by Intramolecular Hydrogen-Bonding Interactions
%U https://acs.figshare.com/articles/dataset/Pyridin_2_yl_Guanidine_Derivatives_Conformational_Control_Induced_by_Intramolecular_Hydrogen_Bonding_Interactions/2581936
%R 10.1021/jo200954c.s004
%2 https://ndownloader.figshare.com/files/4227718
%K series
%K dihedral angle
%K intramolecular interactions
%K 1 H NMR spectra
%K NMR analysis
%K guanidinium salts
%K pyridine N 1 atom
%K derivative
%K guanidinium protons
%K B 3LYP
%K guanidine
%K data
%K Conformational Control Induced
%K pyridine ring
%X The synthesis and conformational analysis of a series
of pyridin-2-yl
guanidine derivatives using NMR, X-ray crystallography, and B3LYP/6-31+G**
theoretical studies are reported. A remarkable difference was observed
in the 1H NMR spectra of the guanidinium salts as compared
with their N,N′-di-Boc protected
and neutral analogues. This difference corresponds to a 180°
change in the dihedral angle between the guanidine/ium moiety and
the pyridine ring in the salts as compared to the Boc-protected derivatives,
a conclusion that was supported by theoretical studies, X-ray data,
and NMR analysis. Moreover, our data sustain the existence of two
intramolecular hydrogen-bonding systems: (i) between the pyridine
N1 atom and the guanidinium protons in the salts and (ii) within the tert-butyl carbamate groups of the Boc-protected derivatives.
To verify that the observed conformational control arises from these
intramolecular interactions, a new series of N-Boc-N′-propyl-substituted pyridin-2-yl guanidines were
also prepared and studied.
%I ACS Publications