Phenolic macrocycle

Phenol, from irradiated benzene, 3 181-182 Phenolic macrocycle, 39 140-141 Phenomenological modeling density-functional theory, 38 465 oxidized (-t3) and reduced (-H) clusters, four-iron clusters, 38 462 64 Phenylacetic acid, irradiation of, 5 201 Phenylalanine... 

Matthews, K. D. Kahwa, I. A. Williams, D. J. Preparation, structure, and luminescence of dinuclear lanthanide complexes of a novel imine-amine phenolate macrocycle. Inorg. Chem. 1994, 33,1382-1387. 

Included in this group of drugs are the benzimidazoles, imidazoUriazoles, tetrahy-dropyrimidines, salicylanilides, substituted phenols, macrocyclic lactones, sulfon-... 

Figure 51. Anionic template synthesis of rotaxane 118 with a bis(phenyl ether) axle. The mechanical bond is formed by reaction of the phenolate-macrocycle complex [32-115] (supramolecular nucleophile) with the semiaxle intermediate 117. 

The reaction of ferrocenecarbaldehyde (98) and resorcinol (99) under acidic conditions gave the phenolic macrocycle (100), which on addition of chlorobromomethane in the presence of a base produced the first redox-active cavitand (141,142) (101) (Scheme 31). An X-ray structural investigation on crystals of (101), obtained from a dichlorometh-ane-diethyl ether solvent mixture, revealed the inclusion of a dichloro-methane guest molecule within the cavitand host cavity (Fig. 23). Related redox-active cavitand host molecules ((102) and (103)) containing ferrocene moieties lining the wall of the cavitand cavity have also been prepared by our group (141, 142). 

Calix[n]arenes, which are phenolic macrocycles (Figure 1.5), were popularized by Gutsche in 1978, although calixarenes date back to Baeyer s work on phenol-formaldehyde chemistry in the ISTOs. " Calix[n]arenes are composed of phenolic units. The phenolic units are linked by methylene bridges at their 2- and 6-positions [meta positions). Gutsche et al. discovered that even-numbered calix[n]arenes ( = 4, 6, 8) were selectively obtained by tuning the reaction conditions for the phenolic derivatives and formaldehyde. 

Macrocycles containing intra-annular carboxylic acids Macrocycles containing intra-annular sulfinic or sulfonic acids Intra-annular phenols 1,3-Diketones... 

The 1,3-xylyl trick was also used for the incorporation of phenols into crown ethers. Three classes of phenols [46a]-[46c] have been investigated. They differ by their substituents in the 4-position. In Table 22 the pX a values of different macrocyclic phenols [46a]-[46c] are compared. The data obtained for the phenol-containing crowns [46a] and [46b] show very little evidence for a macrocyclic effect. No extra stabilization of the protonated (acidic) form by a macrocycle of appropriate ring size was found. The acidities of the macrocyclic phenols [46a] and [46b] were independent of the ring size and comparable to non-macrocyclic analogues. However, the azo-substituted crowns [46c] showed a difference of 0.8 pACg units which was not expected from the pAfa values of [46a] and [46b]. TTiis different behaviour of [46c] is not yet understood. 

A huge group of macrocycles which contain 2,6-disubstituted phenols are the calixarenes [51]-[53]. Their conformation has been investigated intensively (Gutsche, 1989, 1991). In most conformations, however, the phenolic rings are oriented almost vertically in relation to the plane of the macrocydic ring. Therefore the OH functions are not oriented in an intra-annular fashion. Nevertheless the pK values of calixarenes [51] differ from those of other comparable phenols. The reason for this is the... 

In the polyazamacrocyclic phenols [64], an acidic function, the phenol group, has an intra-annular orientation while the basic units, the nitrogen atoms of the macrocycles, have no defined orientation. In water at 25°C, the pATa values of the phenols were measured and compared with those of other macrocyclic and non-macrocyclic phenols (Kimura et al., 1987a,b). Because the nitrogen atoms and the phenol function both possess acid-base properties, more than one pXg value could be measured. By the use of UV measurements, the values of the phenol group could be distinguished from those of the amines. 

When the neutral macrocycles [64] were dissolved in solvents other than water, equilibria between the neutral forms and betaine structures were also found. In ethanol, the equilibrium between a phenol and a betainic... 

A dinuclear iron(ll/Ill) complex bearing a hexadentate phenol ligand displayed moderate activity toward aziridination of alkenes with PhlNTs a large excess of alkene (2,000 equiv. vs PhlNTs) was required for good product yields (Scheme 22) [76]. It is noteworthy that complex 4 is active in the aziridination of aliphatic alkenes, affording higher product yields than copper (11) catalysts with tetradentate macrocyclic ligands [77]. 

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-... 

The 12-membered macrocyclic triamine bearing a phenol pendent (591) was synthesized by one-pot annealation from coumarin and l,7-diamino-4-azaheptane. Upon coordination to Ni, the pendent phenol readily dissociates its proton at acidic pH and becomes a strong fourth donor.1506... 

Macrocyclic Schiff base compartmental ligands (750) (Robson-type ligands) derived from the [2 + 2] condensation of a 2,6-diformyl- or 2,6-diketo-substituted phenol and a diamine are very prominent in dinuclear Ni coordination chemistry.1901-1903 Particular interest lies in magnetic exchange interactions between the adjacent metal ions as well as in bioinorganic chemistry, where such dinuclear complexes have been proposed as synthetic analogues for bimetallosites. 

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