6280-45-1Relevant academic research and scientific papers
Application to photoreactive materials of photochemical generation of superbases with high efficiency based on photodecarboxylation reactions
Arimitsu, Koji,Endo, Ryosuke
, p. 4461 - 4463 (2014/01/06)
A thin film of polystyrene containing 4c was spin-coated on a CaF2 plate and irradiated with 365 nm light. The absorption band arising from the carboxylate of 4c at 1372 cm-1 in the FTIR spectrum decreased after UV irradiation. Radical UV curing materials that are well established in the marketplace have drawbacks because of high volume shrinkage and oxygen inhibition. The anionically cured film showed high transparency and no volume shrinkage, in contrast to a conventional radical UV curing system, which showed large volume shrinkage. This is probably due to relatively low quantum yields for photobase generation and weaker basicity of photo-generated bases, leading to low photosensitivity of photoreactive materials sensitized with photobase generators. Furthermore, many of the photobase generators reported are generally prepared via several synthetic steps.
Gas-phase Reactions of 2-Benzyl- and 2-Benzoyl-phenoxyl Radicals, and of 2-Phenoxybenzyl Radicals: Examples of New Hydrogen-transfer Processes
Cadogan, J. I. G.,Hutchison, H. Susan,McNab, Hamish
, p. 385 - 393 (2007/10/02)
Generation of the 2-benzylphenoxyl radical 23 or the 2-phenoxybenzyl radical 24 by flash vacuum pyrolysis of the ethers 8 or 9, or the oxalate 19, respectively, leads to fluoren-1-ol 22 together with 2-benzylphenol 7 and a low yield of xanthene 21.Pyrolysis of the para-substituted derivatives 11 and 20 gives an analogous distribution of products, including two isomeric methylxanthenes 28 and 29 formed via the spirodienyl 27.The reactions of the corresponding 2-benzoylphenoxyl radicals give information on the mechanism of these processes.Thus the formation of the fluorenones 37 and 43 provides evidence for the hydrogen-abstraction mechanism (Scheme 4) of fluorene formation.Secondly, a detailed study of the ratios of xanthones 41 and 42 under a variety of pyrolysis conditions suggests that such 6-membered-ring products are formed by sigmatropic shifts in the spirodienyl, rather than direct cyclisation of the phenoxyl or benzoyl radicals.
