Polyphenyls, synthesis

Polypeptides (s. a. Tripeptides) —, 1-step synthesis 18, 436 Polyphenyls, synthesis 16, 977 Polyphosphoric acid (s. a. Phosphorus pentoxide/ phosphoric acid) GG"f>0 ... 

Bromo-m-terphenyl in an equal mixture of ether and benzene added at 10° to a slight excess of n-butyllithium in ether, kept an additional 20 min. at 10°, 3-ethoxy-2-cyclohexenone in ether added, stirred 30 min., and decomposed with dil. H2SO4 -> 3-(4-m-terphenyl)-2-cyclohexenone. Y 88%.—This is a step in a polyphenyl synthesis. F. e. and steps s. G. F. Woods et al.. Am. Soc. 82, 5227 (1960) branched polyphenyls s. 82, 5232. 

Polypheny I Ethers. Both alkyl-substituted and iinsubxtiinlcd polypheny ethers are included in this class of synthetic lubricants. General preparation involves the (.llhiian ether synthesis. The unsubstituted polyphenyl ethers have outstanding thermal, oxidative and radiation resistance, however, poor low-temperature characteristics arc a major drawback. Alkyl substitution improves low-temperature viscosity, but detracts from stability. Most lubricant uses are developmental in nature and involve aircrali and aerospace applications. 

Since the thermal degradation in phenylated polyphenyls of the type XXa is caused by the loss of pendant phenyl groups, and since the reported (4, 7, 9, 10, 11, 14, 15) properties of p-polyphenylenes are quite different from those of XXa, the synthesis of an unphenylated polyphenylene by this pathway was of considerable significance. Only a few results employing this reaction have thus far been obtained. [The p-poly-phenylenes reported are black or brown, insoluble, crystalline materials of lower thermal stability than XXa.]... 

Corriu, R.J.P., Masse, J.E, 1972. Activation of Grignard reagents by transition-metal complexes. A new and simple synthesis of trans-stUbenes and polyphenyls. J. Chem. Soc., Chem. Commun. 3,144a-144a. 

The simplest and the most widely-used method for the synthesis of sulfonated ACPs involves sulfonation of different classes of polymers, such as substituted poly-(l,4-phenylenes) [34,35], poly-(p-xylylene [36,37]), poly-(l,4-oxyphenylenes) [38-44], poly(ether ether ketones) (PEEK) [46- 59], polyary-lenefether sulfones) [3,60-74], poly(phenylene sulfides) [75], polyphenyl-quinoxalines [76-79], polybenzimidazoles [80], polyperyleneimides [81] and some other ACPs. 

The method is very effective in the synthesis of several naphthalene, phenanthrene, and other polyphenyl-dimers [100]. 

Speight JG, Kovadc P, Koch FW (1971) Synthesis and properties of polyphenyls and polyphenylenes. Macromol Rev 5 295-386... 

Keywords Cyclophane, Synthesis, Benzenoid Hydrocarbons, Arenes, Polyphenyls. 

Vancomycin is a chlorinated polyphenyl ether antibiotic, with sugar and aminoacid residues, obtained from Streptomyces orientalis. It specifically and strongly binds to the disaccharide peptides that are the raw material from which bacteria build new cell wall. It is still sometimes used clinically for penicillin-resistant organisms. Its aaion resembles that of penicillin in that the synthesis of new cell wall is prevented, so that growing cells quickly die by rupture of the plasma membrane (Anderson et al. 1965). 

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