Synthesis and Photochemistry of Stable Unsaturated Compounds of Group-14 Metals

本研究的目的是合成新的稳定的14族元素不饱和化合物，并揭示其结构和反应。主要结果如下：(1)发现了稳定的二烷基硅烯与二氯甲烷和氯甲基环丙烷的异常反应。通过引用硅烯的双亲性质来解释这一结果。(2)首次观察到电子激发的硅烯与苯衍生物的反应。被激发的亚硅烯应该具有单重态1，1-双自由基的性质。(3)通过详细的理论研究，解决了双(二异丙氨基)硅烯的二聚体结构与实验结果明显不一致的问题。(4)揭示了四(三烷基硅基)二硅烯的E，Z-异构化反应速率和机理。(5)在理论和实验研究的基础上，提出了二硅烯与醇和氯代烷反应的独特机理。(6)新的硅基锂试剂--1，2-d…四(三烷基硅基)二硅烯与锂在四氢呋喃中反应得到了更多的锂硫代二硅烷(1)。(7)以1，2-二锂硫代二硅烷1与酮反应合成了1，3-二硅双环[1.1.0]丁烷。二硅双环丁烷被发现具有独特的倒置σ桥键。(8)合成了具有金属环丙烷型结构的二硅烯-铂配合物，并用X-射线单晶衍射法测定了其结构。(9)首次合成了一种碳类似物未被分离的硅-蝴蝶结化合物(螺戊二烯)。X-射线结晶学和理论计算揭示了分子中独特的螺旋共轭现象。(10)合成了一种稳定的具有反极性的Si=C键的4-硅三富烯，并用X射线单晶学和各种光谱对其进行了表征，这些结果将有助于构建主族元素化学中的结构和成键的新概念，并为未来的功能材料提供基本结构。较少

The aim of our study has been to synthesize novel stable group-14 element unsaturated compounds and to reveal their structure and reactions.The following are the major results: (1) Unusual reactions of stable dialkylsilylene with dichloromethane and chloromethylcyclopropane were discovered. The results were explained by invoking the ambiphilic nature of silylene. (2) The reactions of the electronically excited silylene with benzene derivatives were first observed. The excited silylene should have the nature of the singlet 1,1-biradical. (3) An apparent discrepancy for the dimer structure of bis(diisopropyl-amino)silylene between experiment and theory was solved by the detailed theoretical study. (4) Rates and mechanism of the E,Z-isomerization in tetrakis(trialkylsilyl)disilenes were revealed. (5) Unique mechanisms of the reactions of disilenes with alcohols and chloroalkanes were proposed on the basis of the theoretical and experimental studies. (6) A new silyllithium reagent, a 1,2-d … More ilithiodisilane (1), was prepared by the reaction of a tetrakis(trialkylsilyl)disilene with lithium in THF. (7) A 1,3-disilabicyclo[1.1.0]butane was synthesized using the reaction of the 1,2-dilithio-disilane 1 with a ketone. The disilabicyclobutane was found to have a unique inverted σ bridge bond. (8) A disilene-platinum complex, which has a metallacyclopropane type structure, was synthesized using the reaction of 1 with a dichloroplatinum and its structure was determined by X-ray crystallography. (9) A silicon-bowtie compound (spiropentasiladiene), whose carbon analogs have never been isolated, was first synthesized. The unique spiro-conjugation in the molecule was revealed by X-ray crystallography and theoretical calculations. (10) A stable 4-silatriafulvene having an Si=C bond with inverted polarity was synthesized and characterized by X-ray crystallography and various spectroscopies.All these results will contribute to construct a new concepts of structure and bonding in the chemistry of main-group elements and to offer the basic structures for the future functional materials. Less