Generation of Active Indium Reagent from

新型的铟试剂可用于有机合成。进行了以下反应：(1)氢化铟的生成及其在各种官能团还原中的应用。(2)由氯化铟和氢硅烷合成的新型路易斯酸体系。以方法1为例，采用三丁基氢化锡与InCl_3之间的金属转化法制备氯化二氯铟（Cl_2InH）。氢化铟由于难以生成而很少用于有机合成。这是氢化铟在有机合成中的首次应用。生成的Cl_2InH可以还原各种官能团，如醛、酮、酸氯和烷基酯。特别是，酸卤化物的还原得到了一种作为唯一产物的醛。也可以用烯丙基铟代替氢化铟，与氯化酸选择性反应生成全烯丙基酮。在这些反应中，氧化膦作为配体控制铟试剂的反应性发挥了重要作用。当反应涉及自由基过程时，氢化铟能有效地还原烷基卤化物。特别是在室温下可以进行自由基反应。此外，氢化铟的使用还发生了自由基环化反应。其次，作为方法2的一个例子，氯化铟与氢硅烷结合作为一种新的路易斯酸。因此，芳香烃和羰基化合物之间进行了还原弗里德尔-克拉夫特反应。In-Si体系使酮体脱氧生成烷烃。该方法可以扩大到以脱氧方式引入各种功能的酮类。此外，还可以建立醇的脱氧离子。适用于各种醇，包括芳香族和脂肪族醇。

Novel type of indium reagents could be developed and were applied to organic synthesis. Following reactions were performed. (1)Generation of indium hydride and its application to the reduction of various functionalities. (2)Novel Lewis acid system generated by indium chloride and hydrosilanes.As a example of method 1, dichloroindium chloride(Cl_2InH)could be generated by transmetallation between tributyltin hydride and InCl_3. Indoium hydride have scarcely been used in organic synthesis because of difficulty to their generations. This is the first application of injium hydride in organic synthesis. The generated Cl_2InH could reduce various functional group such as akdehydes, ketones acid chloride and alkyl hakides. In particular, the reduction of acid halide gave an aldehyd as a sole product. In place of indium hydrie, allylic indium also could be generated, which react with acid chloride to give homoallyl ketones selectively. In these reaction, phosphine oxide played an important role as a ligand to control the reactvity of indium reagent. Indium hydride could reduce alkyl halide effectively where the reaction involved radical process. In particular, room temperature radical reacttion could be attained. In addition the use of indium hydride underwent radical cyclization reactions.Secondary, as a example of method 2, indium chloride acted as a novel Lewis acid by the combination with hydrosilanes. Thus reductive Friedel-Crafts reaction between aromatis and carbonyl compounds were performed. The In-Si system enable the deoxygenation of ketones to give alkanes. This method could be enlarged to introduce various functionalities to ketones in deoxygenatice manner. Moreover, deoxygenarion of alcohols could be established.where various alcohols including aromatic and aliphatic ones could be applicable.