Hydroxyl substitution, calculations

Beyer synthesis, 2, 474 electrolytic oxidation, 2, 325 7r-electron density calculations, 2, 316 1-electron reduction, 2, 282, 283 electrophilic halogenation, 2, 49 electrophilic substitution, 2, 49 Emmert reaction, 2, 276 food preservative, 1,411 free radical acylation, 2, 298 free radical alkylation, 2, 45, 295 free radical amidation, 2, 299 free radical arylation, 2, 295 Friedel-Crafts reactions, 2, 208 Friedlander synthesis, 2, 70, 443 fluorination, 2, 199 halogenation, 2, 40 hydrogenation, 2, 45, 284-285, 327 hydrogen-deuterium exchange, 2, 196, 286 hydroxylation, 2, 325 iodination, 2, 202, 320 ionization constants, 2, 172 IR spectra, 2, 18 lithiation, 2, 267... 

The second separation method involves n.O.e. experiments in combination with non-selective relaxation-rate measurements. One example concerns the orientation of the anomeric hydroxyl group of molecule 2 in Me2SO solution. By measuring nonselective spin-lattice relaxation-rat s and n.0.e. values for OH-1, H-1, H-2, H-3, and H-4, and solving the system of Eq. 13, the various py values were calculated. Using these and the correlation time, t, obtained by C relaxation measurements, the various interproton distances were calculated. The distances between the ring protons of 2, as well as the computer-simulated values for the H-l,OH and H-2,OH distances was commensurate with a dihedral angle of 60 30° for the H-l-C-l-OH array, as had also been deduced by the deuterium-substitution method mentioned earlier. 

Drago and coworkers have also calculated the enthalpy values for the formation of many complexes or hydrogen bonds by NMR and calorimetric techniques. For example, in a series of phenols or t-BuOH, they observed the IR frequency shifts (Avqh) of the hydroxyl compounds and found that a linear relationship exists between bases and individual acids. In Table 7 shows some AH values calculated by equation 2, and Avqh values of t-BuOH" " while in Table 8 frequency data Avq of various substituted phenols and the AH values are given. 

An irreversible dyotropic rearrangement of fluoro-substituted tris(silyl)hydroxyl-amines (127) (128) has been reported and ab initio and density functional calculations for model compounds have confirmed the dyotropic course of this rearrangement. ... 

Kinetic calculations accord well with the experimental data only if o-DNB anion-radical is considered as the particle undergoing substitution of hydroxyl group for the nitro group (Abe and Ikegame 1978). 

Schindler and coworkers verified the formation of hydroxyl radicals kinetically and further RRKM calculations by Cremer and coworkers placed the overall concept on a more quantitative basis by verifying the measured amount of OH radical. An extensive series of calculations on substituted alkenes placed this overall decomposition mechanism and the involvement of carbonyl oxides in the ozonolysis of alkenes on a firm theoretical basis. The prodnction of OH radicals in solution phase was also snggested on the basis of a series of DFT calculations . Interestingly, both experiment and theory support a concerted [4 4- 2] cycloaddition for the ozone-acetylene reaction rather than a nonconcerted reaction involving biradical intermediates . 

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