3739-81-9Relevant academic research and scientific papers
Synthesis and intramolecular ring transformation of: N, N ′-dialkylated 2,6,9-triazabicyclo[3.3.1]nonadienes
Ito, Akitaka,Nakaike, Yumi,Nishiwaki, Nagatoshi,Yokoyama, Soichi,Yoshida, Yusuke
, p. 9109 - 9116 (2020)
The first and facile synthesis of N,N′-dialkylated 2,6,9-triazabicyclo[3.3.1]nonadienes was achieved by the [4 + 4] self-condensation of β-formyl-β-nitroenamine in the presence of ammonium acetate. The 2,6- A nd 2,9-dialkylated products were found to be interconvertible when dissolved in a solvent. This isomerization proceeds through intramolecular ring transformation via a common intermediate under equilibrium. This journal is
Infrared Study of Hydrogen-Bonded Complexes Involving Phenol Derivatives and Polyfunctional Bases. 2. 3-Methyl-4-pyrimidone, 1-Methyl-2-pyrimidone, 1,4,4-Trimethylcytosine, and 1,3-Dimethyluracil
Kasende, O.,Zeegers-Huyskens, Th.
, p. 2636 - 2641 (1984)
In this work, the electron-donating properties of 3-methyl-4-pyramidone (I), 1-methyl-2-pyramidone (II), 1,4,4-trimethylcytosine (III), 1,3-dimethyluracil (IV), and pyrimidine (V) have been studied by infrared spectrometry, using the phenol derivatives as reference acids.The thermodinamic parameters (K, -ΔH, ΔS) determined in 1,2-dichloethane (1,2-DCE) are ordered according to III > II > IV > V, the same order as that predicted from the pKa value, with the exception of IV.For the same enthalpy of complex formation, the ΔνOH values were markedly higher for V than for the complexes involving the other bases; this fact and the frequency lowering of the νC=O vibration clearly show that for compounds I-IV the carbonyl group is the preferred H-bond site.For IV, the infrared data suggest that complex formation takes place on the O4 atom in agreement with the lower ionization potential of the n(O4) electrons.As shown by the X-ray diffraction method and the infrared spectra available in the literature, protonation takes place on the nitrogen atom for I-III and on the O4 atom for IV.This shows that, with the exception of IV, the preferred H-bonding site is not the preferred site of protonation.The intermolecular streetching vibrations ν? are observed between 130 and 110 cm-1 and the corresponding force constants k? are calculated by the Lippincott-Schroeder potential function.The k? values are compared with those of hydrogen bonds involving nitrogen and sulfur atoms.It is shown that, for the same enthalpy of complexation, the k? values are related to the extension of the lone-pair electrons of the base.
Formylnitroenamines: Useful building blocks for nitrated pyridones and aminopyridines with functional groups
Nakaike, Yumi,Hayashi, Daisuke,Nishiwaki, Nagatoshi,Tobe, Yoshito,Ariga, Masahiro
experimental part, p. 325 - 334 (2009/03/12)
β-Formyl-β-nitroenamines 1 possess both an electrophilic formyl group and a nucleophilic amino group and, therefore, serve as C3N1 building blocks having a nitro group to afford nitropyridones and aminonitropyridines with a functional group at the 3-posit
