Synthesis of poly(aryl ether) dendrimers using an aryl carbonate and mixtures of metal carbonates and metal hydroxides

✍ Scribed by Coromoto A. Martínez; Allan S. Hay

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 281 KB
• Volume: 35
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19970715)35:9<1781::aid-pola19>3.0.co;2-1

✦ Synopsis

Four generations of poly(aryl ether) dendrimers containing aryl sulfide or aryl sulfone groups, and aryl fluoride terminal functionality, have been synthesized using the divergent initiator core method and bis(4-fluorophenyl)sulfone as the core precursor. The strategy is based on the divergent approach and an activation/condensation sequence that involves oxidation of the aryl sulfide group and the displacement of the activated halide moiety by a phenolate ion. The phenolate is easily generated in situ from an aryl carbonate. No reaction intermediates were detected when the condensation reaction was carried out utilizing a very active metal carbonate, such as cesium carbonate, in conjunction with magnesium hydroxide or calcium carbonate which removes some of the fluoride ions formed. The samples were characterized by HPLC, MALDI-TOF-MS, NMR, and SEC. Imperfections in some of the molecules of the dendrimers, formed by reaction of the core precursors with an impurity present in the phenol, were also identified by MALDI-TOF-MS.