Study on the Novel Radical Reactions with Hypervalent Iodine Compounds

自由基反应是有机合成中最常用的方法之一。因此，我们开展了与三价碘化合物的新型自由基反应的研究。结果发现，在钨灯照射下，芳环上带电子基团的(二酰氧基)芳烃加速了自由基反应，1)在二硫化物存在下，羧酸转化为相应的硫化物，2)芳香羧酸转化为相应的伽马或β-内酯，3)含芳环的醇转化为相应的环醚，4)含芳环的胺转化为相应的环胺，这些反应通过形成碳、氧和氮中心自由基来进行，从而以较好的产率获得操作简单的产物。在自然界中，含有氧原子和氮原子的重要环状化合物种类繁多。因此，本方法对这些天然产物的制备是非常有用的。这些成果于1995年在三种国际期刊上发表，其他论文正在为向这些期刊投稿做准备。

Radical reactions are one of the most useful methods for organic synthesis. Therefore, the study on the novel radical reactions with trivalent iodine compounds has been carried out. As a result, it was found that (diacyloxyiodo) arenes which has electron-donating group on a aromatic ring accelerated the radical reactivities under the irradiation with tungsten lamp as shown below,1) conversion of carboxylic acids to the corresponding sulfides in the presence of disulfides,2) conversion of aromatic carboxylic acids to the corresponding gamma-or delta-lactones,3) conversion of alcohols bearing a aromatic ring to the corresponding cyclic ethers,4) conversion of amines bearing a aromatic ring to the corresponding cyclic amines,These reactions proceed via the formation of carbon-, oxygen-, and nitrogen-centered radicals to give the products with a simple operation in good yields. In nature, there are many kinds of important cyclic compounds containing oxygen and nitrogen atoms. Therefore, the present method is very useful for the preparation of these natural products. These results were published in three international Journals in 1995, and the other papers are in preparation for the contribution to the Journals.