Research on The Novel Photo-rearrangement And Photo-fragmentation of Arylated Cyclic Peroxides

1)采用新颖的电子转移光氧化方法，制备了多种芳基化1，2-二氧戊环和1，2-二氧杂环己烷。2）发现上述环状过氧化物的O-O键断裂的双自由基中间体在直接光照下发生重排和断裂。研究还发现，具有对甲氧基苯基等给电子芳香族取代基的底物，一般都能发生芳基位移; 3）发现在环状过氧化物的热反应中，二氧代双自由基中间体机理和类协调键断裂机理同时起作用; 4）发现C-O键断裂的阳离子自由基中间体在吡喃盐敏化的光电子转移反应中发生重排和芳构化。5）Fe（Ⅱ）和Fe（Ⅱ）诱导的环状过氧化物的非光化学单电子转移还原反应（III）进行溴化物。结果表明，O-O键断裂的单氧自由基中间体发生了重排和断裂。

1) Variety of arylated 1,2-dioxolanes and 1,2-dioxanes were prepared by using original modified methods of electron transfer photo-oxygenation. As a result, new synthetic methods were established for the unknown derivatives of above cyclic peroxides while improvements of the yields for the known derivatives were performed.2) It was found that O-O bond cleaved diradical intermediates of above cyclic peroxides in the direct photo-irradiation occurred rearrangements and fragmentations. It was also found that aryl shift generally proceeded for the substrates possessing electron donating aromatic substituents such as p-methoxyphenyl group.3) It was found that the dioxyl-diradical intermediate mechanism and the concerted-like bond cleavage mechanism were simultaneously operated in the thermal reaction of the cyclic peroxides.4) It was found that C-O bond cleaved cation radical intermediates occurred rearrangements and fragrnentations in the pyrylium salt sensitized photo-electron transfer reactions.5) Non-photochemical single electron transfer reduction of the cyclic peroxides induced by Fe(II)and Fe(III) bromides were performed. As a result, it was found that O-O bond cleaved mono-oxyl-radical intermediates underwent rearrangements and fragmentations.