Persulfate-amine systems

Several articles [7,8] have reported that a persulfate-amine system, particularly persulfate-triethanol amine and persulfate-tetramethylethylenediamine (TMEDA) can be used as redox initiators in aqueous solution polymerization of vinyl monomers. Recently, we studied the effect of various amines on the AAM aqueous solution polymerization and found that not only tertiary amine but also secondary and even primary aliphatic amine and their polyamines can promote the vinyl polymerization as shown in Table 6 [40-42]. 

Organic peroxide-aromatic tertiary amine system is a well-known organic redox system 1]. The typical examples are benzoyl peroxide(BPO)-N,N-dimethylani-line(DMA) and BPO-DMT(N,N-dimethyl-p-toluidine) systems. The binary initiation system has been used in vinyl polymerization in dental acrylic resins and composite resins [2] and in bone cement [3]. Many papers have reported the initiation reaction of these systems for several decades, but the initiation mechanism is still not unified and in controversy [4,5]. Another kind of organic redox system consists of organic hydroperoxide and an aromatic tertiary amine system such as cumene hydroperoxide(CHP)-DMT is used in anaerobic adhesives [6]. Much less attention has been paid to this redox system and its initiation mechanism. A water-soluble peroxide such as persulfate and amine systems have been used in industrial aqueous solution and emulsion polymerization [7-10], yet the initiation mechanism has not been proposed in detail until recently [5]. In order to clarify the structural effect of peroxides and amines including functional monomers containing an amino group, a polymerizable amine, on the redox-initiated polymerization of vinyl monomers and its initiation mechanism, a series of studies have been carried out in our laboratory. 

Although the ECL phenomenon is associated with many compounds, only four major chemical systems have so far been used for analytical purposes [9, 10], i.e., (1) the ECL of polyaromatic hydrocarbons in aqueous and nonaqueous media (2) methods based on the luminol reaction in an alkaline solution where the luminol can be electrochemically produced in the presence of the other ingredients of the CL reaction (3) methods based on the ECL reactions of rutheni-um(II) tra(2,2 -bipyridinc) complex, which is used as an ECL label for other non-ECL compounds such as tertiary amines or for the quantitation of persulfates and oxalate (this is the most interesting type of chemical system of the four) and (4) systems based on analytical properties of cathodic luminescence at an oxide-coated aluminum electrode. 

More importantly, this silver system catalyzes the intermolecular amination of hydrocarbons, as shown in Table 6.3. In addition to animating weaker benzylic C-H bonds, stronger aliphatic C-H bonds such as those in cyclohexane were also reactive. Although yields with more inert hydrocarbons were modest with the bathophenan-throline system, the discovery of the first silver-catalyzed intermolecular amination opens opportunities for further developments. This reaction favored tertiary cyclic sp3 C-H bonds over secondary cyclic sp3 C-H bonds, and showed limited success with simple linear alkanes. No conversion was observed with any aromatic C-H bonds. The compound NsNH2 was tested as the nitrene precursor with different oxidants. The use of PhI(OAc)2 as oxidant gave the expected amination product with a lower yield, while persulfate and peroxides showed no reactivity. 

The only jU-superoxo complexes to have been characterized are those which contain cobalt. They are readily prepared by treatment of the corresponding /i-peroxo complexes with strong oxidants. Thompson and Wilmarth observed that MnO, HOCl, Br2, BrOf and NOf are all effective oxidants toward [(en) Co(/r-NH2,02)Co(en)2] in acidic solution whereas Fe ", HjOj, Ag" " and CtjO are not. In other systems CI2, Pb02, persulfate and Ce in nitric acid solution have also effected oxidation. A number of well-characterized //-superoxo cobalt(III) complexes are listed in Table 55. There are no reports of /i-superoxo complexes containing Schiffbase ligands and all that are known contain either terminal amine or cyano groups. 

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