Stereochemical and conformational exchanges in N,N'-di(2-pyridyl)formamidines: An X-ray and (1)H NMR study.
The solid state structure of N,N'-di(2-pyridyl)formamidine displays a four-hydrogen-bonded dimer. In solution, two isomers are observed, one of which is selected and amplified either by crystallization or by adding protons. Solution state analysis of N,N'-di(2-pyridyl)formamidines reveals the presence of the uncommon Z formamidine isomer, which equilibrates with the E-isomer with an activation energy of 90 kJ mol(-1) in CDCl(3).
Xing
Liyan
L
Department of Chemistry, Queen's University, 90 Bader Lane, Kingston ON K7L3N6, Canada.
Wiegert
Charline
C
Petitjean
Anne
A