Arylethers

A large variety of newer poly(ether imide)s has been described. Included among these are perfluorinated polymers (96), poly(ester ether imide)s (97), poly(ether imide)s derived from A/,Ar-diamino-l,4,5,8-naphthalenetetracarboxyHcbisimide (98), and poly(arylene ether imide ketone)s (99). In addition, many other heterocyHc groups have been introduced into polyether systems, eg, poly(pyrazole ether)s (100) and poly(aryl ether phenylquinoxaLine)s (101) poly(aryl ether oxazole)s with trifluoromethyl groups (102) and polyethers with other heterolinkages, eg, poly(arylether azine)s (103). 

The results presented in this review concern this metal-catalyzed mechanism. Depending on the nature, anionic or neutral, of the different nucleophiles, the result of the arylation can be a neutral substitution product or a cationic one, which most often, in the last case, undergoes an evolution, for example (starting form a phosphite) to a phosphonate or, after deprotonation, to an arylamine or to an arylether (Fig. 2). 

With alcohols or more often with alcoholates (refs. 51 - 56) or phenolates (refs. 57 - 64) the arylethers are formed. Typically, one of the Ullmann reactions is corresponding to the diarylethers synthesis. 

Very interesting antenna systems have been constructed by functionalizing the chain ends of a poly(arylether) convergent dendritic backbone with cou-marin-2 A =435 nm) and its focal point with coumarin-343 X =49Q nm) [33] dendrimer 8 represents the fourth generation. 

Figure 6. Convergent synthesis of poly(arylether) dendrimers by Frechet et al.

Poly(arylether ketone), conducting, 7 524 Poly(aryl ether ketone)s, sulfonation reaction of, 23 717-718 Poly(di-n-alkylsilanes), thermochromic materials, 6 619... 

Alkylarylether derivatives—alkylarylether sulfates, -sulfonates, -phosphates and di-alkyl arylether-carboxylates... 

Arylether Sulfone Oligomers with Acetylene Termination from the Ullman Ether Reaction... 

The most convenient method of preparing the flexible (low Tg) system is to employ the Ullmann ether reaction of dibromobenzene and aromatic bis-diols followed by catalytic replacement of the bromine atoms by terminal acetylene groups. A host of commercially available bis-diols have been used in the synthesis with both meta and para dibromobenzene. Low Tg arylether oligomers have been prepared containing sulfone, sulfide, carbonyl, isopropyl and perfluoroisopropyl groups in the backbone (9). 

The objectives of this work were to synthesize a series of arylether sulfone oligomers with an increased chain length between reactive sites by the proposed synthetic route. In addition, it was to be determined if the products obtained by this route would have initial glass transition temperatures near or below room temperature while having cured Tg s in the 300-350°F range of epoxides. 

Figure 1. Reaction sequence for AT arylether sulfone oligomers.

I 5 Anodic Reactions of Alkanes, Alkenes, and Aromatic Compounds Tab. 12 Anodic coupling of arylethers... 

Kinetic studies of the acetylation of several arylethers were carried out over HBEA zeolites. The main conclusion is that the rate and stability of the reactions are determined by the competition between reactant(s) and product(s) molecules for adsorption within the zeolite micropores. This competition shows that the autoinhibition of arene acetylation, that is, the inhibition by the acetylated products, and also by the very polar acetic acid product is generally observed. This effect is much more pronounced with hydrophobic substrates such as methyl and fluoro aromatics than with hydrophilic substrates because of the larger difference in polarities between substrate and product molecules. 

The trifluoromethyl group is found in a wide variety of pharmaceuticals. Besides its effect on the electron density, its high lipophilicity improves transport characteristics in vivo and facilitates lower dosage rates. F for F isotopic exchange reaction has been used to synthesize [l- F]l,l-difluoro-2,2-dichloroethyl-arylethers. The substitution proceeds in good to excellent yields (> 85 %) and is strongly dependent on the reaction conditions. Substitution occurs even at room temperature in DMSO or in acetonitrile containing up to 20% of water (Scheme 61) [247]. 

Nitromifene (85) is such an agent. A Grignard reaction of arylether S2 and ketone leads to tertiary carbinol Tosic acid dehydration leads to a mixture of and stilbenes which constitute the antiestrogen, nitromifene (85). ... 

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