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1. The chemical shift of the OH group of the phenol monomer was determined. 2. In phenolinert solvent systems a monomer-trimer equilibrium is observed, with the exception of low concentrations of phenol (~0.03 mole fraction). 3. The chemical shift of the signal of the OH group of the phenol trimer depends on the temperature. 4. The solvent CCl4 is not entirely inert. 5. The constants and thermodynamic parameters of association in systems of phenol and in inert solvent were determined. 6. In all the systems studied the enthalpy remains constant, while the entropy varies from system to system.

The δ (C13) values of the ring carbon atoms for the C13-NMR spectra of 3-methylsydnone and 3-methylsydnoneimine, described for the first time, are compared with the values calculated by the Karplus-Pople method. The interrelationship between the δ(C13) values of conjugated carbocycles, heterocycles, alkenes, and a number of carbonyl-containing compounds and the effective charges of the corresponding carbon atoms calculated by the complete neglect of differential overlap (CNDO/2) method is analyzed thoroughly.

1. The thermodynamic parameters of the reactions for the formation of the complexes of p-chloro- and p-fluorophenol with a number of oxygen-containing donors (pyridine N-oxide, phosphoryl derivatives, triethylamine) were determined. The thermodynamics of these reactions obeys the linear relation between ΔH° and ΔS° that is general for donor-acceptor complexes. 2. The chemical shifts of the hydroxyl protons of the monomeric p-chloro- and p-fluorophenol molecules and of their complexes were determined. Based on an analysis of these shifts it was concluded that the formation of the hydrogen bond O-H... D leads to a decrease in the electron density on the hydrogen atom, which is greater the higher the energy of the H bond (in the energy range from 0 to 12 kcal/mole).