Crystal structure phenols

O. J. Wchrhahn and M. v. Stackcl-berg. Naturwissenschaften 41, 358 (1954). Crystal structure phenol, occlusion complexes. 

The crystalline structure of bis-phenol A polymers has been thoroughly studied by Prietschk and some of the data he obtained on the crystal structure are summarised in Table 20.1. 

Table 20.1 Crystal structure date of bis-phenol A polycarbonates (after Prietschic) ...

Generally the name of a compound should correspond to the most stable tautomer (76AHCS1, p. 5). This is often problematic when several tautomers have similar stabilities, but is a simple and reasonable rule whose violation could lead to naming phenol as cyclohexadienone. Different types of tautomerism use different types of nomenclature. For instance, in the case of annular tautomers both are named, e.g., 4(5)-methylimidazole, while for functional tautomerism, usually the name of an individual tautomer is used because to name all would be cumbersome. In the case of crystal structures, the name should reflect the tautomer actually found therefore, 3-nitropyrazole should be named as such (97JPOC637) and not as 3(5)-nitropyrazole. 

Goff (54) synthesized an Fe(III) porphyrin with a 2-hydroxyphenyl group at one meso position (35, Fig. 12a). Under basic conditions, the system spontaneously dimerizes due to phenolate-Fe(III) coordination. The complex is very stable and was isolated and fully characterized. In the solid state, the X-ray crystal structure confirmed the structure of the assembly as a macrocyclic head-to-tail dimer with two intermolecu-... 

Fig. 10.7 Crystal structure of com pounds 4 stick representation of H-bond (dotted lines) superstructures of (A) phenyl, (B) indole, (C) phenol ureido-silsesquioxanes H atoms were omitted for clarity.

The steric bulk of the perfluoroalkyl group can be demonstrated by examining crystal structures of suitable compounds. For example, the crystal structure of the para-substituted phenol clearly shows the size of the C6F13 group with respect to the aromatic ring (Figure 3.5). 

Krasnov, F.A. et al., Phenolic components of Empetrum nigrum extract and the crystal structure of one of them, Chem. Nat. Compd., 36, 493, 2000. 

The oxidation of phenols forming aryloxyl radicals was first recognized by Pummerer and Frankfurter in 1914," who reacted 2,2 -dihydroxy-l,l -binaphthyl with ferricyanide, and isolated dimers and trimers of the radical 20 (equation 8), which was later observed by ESR." Many further examples were studied by Goldschmidt, Muller, and others," and an X-ray crystal structure confirmed dimer formation with C—O bonding at the 4-position for 3-bromo-2,4,6-triphenylphenoxyl. ... 

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