Tezuka

End-functional polymers, including telechelic and other di-end functional polymers, can be produced by conventional radical polymerization with the aid of functional initiators (Section 7,5.1), chain transfer agents (Section 7.5.2), monomers (Section 7.5.4) or inhibitors (Section 7.5.5). Recent advances in our understanding of radical polymerization offer greater control of these reactions and hence of the polymer functionality. Reviews on the synthesis of end-functional polymers include those by Colombani,188 Tezuka,1 9 Ebdon,190 Boutevin,191 Heitz,180 Nguyen and Marechal,192 Brosse et al.rm and French.194... 

Tezuka s group (Tezuka and Ando, 1985 Tezuka et al., 1986) was able to isolate and characterize the benzenediazo ether of 1-naphthol (6.10). They stirred a solid mixture of the molecular complex 6.9 formed between an a-azohydroperoxide acid and benzene with an excess of 1-naphthol at room temperature in the dark for several hours. The separation of this solid by thin layer chromatography (silica gel, with a benzene-ethyl acetate mixture [9 1] as eluent) afforded the diazo ether 6.10 as a yellow oil in 17 % yield, together with 4- and 2-phenylazo-l-naphthol (6.11 and 6.12, 4% and 42%, respectively), 4-phenylbenzaldehyde (32%), benzoic acid (23%), and traces of other compounds (Scheme 6-6). Higher yields of the diazo ether (up... 

In the context of their new synthetic route to arenediazo phenyl ethers (see Sec. 6.2), Tezuka et al. (1987 a, 1989) investigated the reaction products of phenyldi-azo 1-naphthyl ether (12.10) under various conditions. When an acetonitrile solution of the diazo ether 12.10 was kept standing at room temperature for one week in the dark, the 4- and 2-phenylazo-l-naphthol isomers (12.11 and 12.12) were formed in 48% (20%) and 9% (8%) yields respectively. In the presence of acid (aqueous HC1 or H2S04) or of various bases (aqueous NaOH, pyridine, aniline, or sodium acetate) the yields of the azo products are much lower, but higher proportions of biphenyl, 1-naphthol, and phenol are formed. The crosscoupling product l-phenylazo-2-naphthol was not detected when the reaction was carried out in the presence of 2-naphthol. As this mechanistic test reaction gave rather low yields of the two azo compounds 12.11 and 12.12 in the presence and absence of 2-naphthol,... 

Tezuka, Y., Kazama, H., Imai, K. IUPAC 5th Int. Symp. on Ring-Opening Polymerization, Proc., p. 95, Blois, France (1986)... 

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