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Geometry phenols

Repeat your analysis fox phenoxy radical. Instead of charge, focus on the spin density. Calculate the delocalization energy using phenoxy radical at phenol geometry. Is it of the same order of magnitude as that for phenoxy anion Explain. [Pg.40]

Compare the geometries of triplet and ground state singlet anthrone. Where do they differ the most Focus on the carbonyl group. Has the CO bond distance altered Does the molecule incorporate a fully-developed CO n bond (as in ground state singlet anthrone), or a single bond (as in phenol) Is the carbonyl carbon planar or puckered Rationalize your observations. [Pg.261]

Only the hydrophobic and steric terms were involved in these equations. There are a few differences between these equations and the corresponding equations for cyclo-dextrin-substituted phenol systems. However, it is not necessarily required that the mechanism for complexation between cyclodextrin and phenyl acetates be the same as that for cyclodextrin-phenol systems. The kinetically determined Kj values are concerned only with productive forms of inclusion complexes. The productive forms may be similar in structure to the tetrahedral intermediates of the reactions. To attain such geometry, the penetration of substituents of phenyl acetates into the cyclodextrin cavity must be shallow, compared with the cases of the corresponding phenol systems, so that the hydrogen bonding between the substituents of phenyl acetates and the C-6 hydroxyl groups of cyclodextrin may be impossible. [Pg.79]

Alcohols and phenols have nearly the same geometry around the oxygen atom as water. The R-O—H bond angle has an approximately tetrahedral value (109° in methanol, for example), and the oxygen atom is sp3-hybridized. [Pg.602]

Another elegant example of the thermal generation and subsequent intramolecular cycloaddition of an o-QM can be found in Snider s biomimetic synthesis of the tetracyclic core of bisabosquals.2 Treatment of the starting material with acid causes the MOM ethers to cleave from the phenol core (Fig. 4.3). Under thermal conditions, a proton transfer ensues from one of the phenols to its neighboring benzylic alcohol residue. Upon expulsion of water, an o-QM forms. The E or Z geometry of the o-QM intermediate and its propensity toward interception by formaldehyde, water, or itself, again prove inconsequential as the outcome is decided by the relative thermodynamic stabilities among accessible products. [Pg.91]

A tridentate SNO ligand coordinates with a bipyridine to give ((2,2 -bipyridine)[2-(2-mercapto-phenyl)iminophenoxy])zinc. The monomeric complex has a distorted trigonal bipyramidal geometry with a phenolate and a thiolate coordinated. The synthesis was carried out electrochemically from anodic zinc in the presence of a disulfide-linked ligand precursor.867... [Pg.1224]

N40 donor set ligands with pyridyl and phenolic arms form mononuclear complexes with approximately trigonal-bipyramidal coordination geometries.888... [Pg.1227]

A. Westphal, C. Jacoby, C. Ratzer, A. Reichelt, and M. Schmitt, Determination of the intermolecular geometry of the phenol methanol cluster. Phys. Chem. Chem. Phys. 5, 4114 4122 (2003). [Pg.50]

What are the main error sources in PAC experiments One of them may result from the calibration procedure. As happens with any comparative technique, the conditions of the calibration and experiment must be exactly the same or, more realistically, as similar as possible. As mentioned before, the calibration constant depends on the design of the calorimeter (its geometry and the operational parameters of its instruments) and on the thermoelastic properties of the solution, as shown by equation 13.5. The design of the calorimeter will normally remain constant between experiments. Regarding the adiabatic expansion coefficient (/), in most cases the solutions used are very dilute, so the thermoelastic properties of the solution will barely be affected by the small amount of solute present in both the calibration and experiment. The relevant thermoelastic properties will thus be those of the solvent. There are, however, a number of important applications where higher concentrations of one or more solutes have to be used. This happens, for instance, in studies of substituted phenol compounds, where one solute is a photoreactive radical precursor and the other is the phenolic substrate [297]. To meet the time constraint imposed by the transducer, the phenolic... [Pg.201]


See other pages where Geometry phenols is mentioned: [Pg.31]    [Pg.31]    [Pg.257]    [Pg.475]    [Pg.172]    [Pg.40]    [Pg.57]    [Pg.82]    [Pg.68]    [Pg.275]    [Pg.320]    [Pg.400]    [Pg.412]    [Pg.414]    [Pg.39]    [Pg.101]    [Pg.63]    [Pg.268]    [Pg.634]    [Pg.311]    [Pg.7]    [Pg.17]    [Pg.14]    [Pg.440]    [Pg.441]    [Pg.1149]    [Pg.1224]    [Pg.291]    [Pg.14]    [Pg.308]    [Pg.163]    [Pg.175]    [Pg.54]    [Pg.63]    [Pg.430]    [Pg.193]    [Pg.299]    [Pg.98]    [Pg.200]    [Pg.23]    [Pg.224]    [Pg.273]    [Pg.50]   
See also in sourсe #XX -- [ Pg.457 ]




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