Diphenyliodonium hexafluorophosphate

Figure 3.94. Waveguide structures manufactured by TP initiated polymerization of methyl methacrylate in the presence of a coumarin derivative and diphenyliodonium hexafluorophosphate as TP initiator using a 500-pW Ti sapphire femtosecond laser at 800 nm, equipped with a 0.65 NA microscope objective and a scanning speed of 40 pm/s. (a) Channel waveguide (2 pm), (b) T-shaped waveguide (signal input A signal output B probe signal C), and (c) directional coupler (coupling length is about 30 pm). (From Ref. [135] with permission of the Institute of Physics.)...

The arylsulfonium metal halide complex salts are not readily available. Triphenylsulfoniurn hexafluorophosphate can be prepared from diphenyliodonium hexafluorophosphate by heating with phenyl sulfide, as described by Knapczyk and McEwen ( ), or by reaction of phenyl magnesium bromide with diphenyl sulfoxide followed by reaction with hexafluorophosphoric acid according to the procedure of Wildi, Taylor and Potratz (60). 

TABLE 9 Effect of Hydrogen Atom Donors on Quantum Yield for Benzophenone Sensitized Photolysis of Diphenyliodonium Hexafluorophosphate [60a]... 

Synthesis. Diphenyliodonium hexafluorophosphate, Ph2lPF6, and triphenylsulfonium hexafluoroantimonate, PhaSSbFe, were synthesized using literature procedures (25). Tetra-n-butylammonium hexafluorophosphate, TBAPFe, was obtained by direct metathesis between tetra-n-butylammonium bromide (99%) and potassium hexafluorophosphate (tech.), KPFe. 

Carbonylbis(7-diethylaminocoumarin)(KC) Diphenyliodonium hexafluorophosphate(DPI) Figure 4.12. Chemical structures of photosensitizer (PS) and photoinitiator (PI) for this study. 

Show the mechanism of one-electron transposition initiation with chemical equations based on a free-radical oxidation by diphenyliodonium hexafluorophosphate. (Let the source of the free-radical be photodecomposition of methyl benzoin ether.)... 

The values of BP and BTf were smaller than that of diazo compounds with diethylamino substituent (DED) and close to that of p-diazodiphenylamine (DPD) which is used as the photosensitive emulsion for screen printing plates. The value with BP is three times as large as that of diphenyliodonium hexafluorophosphate (IP). 

Still another example is an initiating system composed of 7-diethylamino-3 -(2 -N-methyl-benzimidazolyl)-coumarin and diphenyliodonium hexafluorophosphate. This composition initiates the polymerization of methyl methacrylate in visible light. After the dye absorbs flic light energy, quick electron transfer takes place from the dye to the iodonium salt to produce free radicals. " The light induced reaction is claimed to occur mainly through the excited singlet state of the coumarin and results in low sensitive to O2. The fluorescence of the coumarin compound was reported to be quenched efficiently by the iodonium salt. " The reaction was observed to be in accord with the Stem-Volmer equation. The influence of the concentration of coumarin on the polymerization rate of methyl methacrylate led to the conclusion that the free radicals from coumarin act mainly as chain terminators. ... 

The main polymer is bis(epoxypropyl)bisphenol A ether. N,N -bis(4-diethylamino)benzylidene diaminomaleonitrile (BAE) is used as the photosensitizer. l,4-Bis[4 (N,N-di-n-butylammo)styryl]-2 -dimethoxybenzene(BSDMB) is used with DPIF (diphenyliodonium hexafluorophosphate) as the photoacid generator (PAG). 

Examples of additives are the following EA = iodonium salt, e.g. diphenyliodonium hexafluorophosphate (more rarely, a sulfonium salt) and related derivatives [113], alkyl halide, e.g. phenacyl bromide [1.14] and triazine, e.g. 2,4,6-tris(trichloromethyl)-l,3,5-triazine ED = borate disulfide, group IVb dimetal [1.15] HD = alcohol, THE, thiol, benzoxazine, aldehyde, acetal, silane (e.g. tris(trime1hylsilyl)silane = (TMS)3Si-H) [1.16]), germane, borane, stannane, alkoxyamine, silyloxyamine, polymer substrate, etc. EPD = amine [1.17], thiol, etc. The generated radicals (e.g. Ph, R, RsSi, RR C R R in [1.13]-[1.17] ) are the initiating species. Efficient novel or newly modified dye structures in the Dye/amine, Dye/iodonium salt or Dye/silane two-component PISs have been proposed within the last 4 years (see section 1.3.5). 

Mah S, Yamamoto Y, Hayashi K. Radiation-induced cationic polymerization of a-methylstyrene enhanced by diphenyliodonium hexafluorophosphate. Macromolecules 1983 16 681-685. 

Synthesis of Triazinium Salts. 1,2,3-Triazines 5 could be phenylated using diphenyliodonium hexafluorophosphate (la) in the presence of catalytic Cul (eq A) ... 

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