Activation of Small Inert Molecules

该研究项目的目标是利用地球上丰富的小惰性分子，如氮气和甲烷，以及二氧化碳的化学转化，二氧化碳在大气中的增加是由于人类使用化石燃料而产生的，并且正在成为全球范围内严重的环境问题。这是开发以二氧化碳和甲烷为简单碳源、二氮为简单氮源合成有价有机化合物的理想化学工艺的基础和基础研究。这些惰性小分子的有效活化和化学利用是化学领域最具挑战性的课题之一。本项目的主要成果如下：1)钼钨膦配合物中的配位二氮在较低的条件下通过一系列反应转化为吡咯和氨基吡咯等氮杂环化合物。用钛系合成了以二氮为原料的吲哚衍生物。这些结果将开辟一个新的固氮化学，直接从分子氮制备各种有机氮化合物。二氧化碳在铜电极上的电化学还原产生甲烷、乙烷和乙醇。该反应是通过在电极上形成作为中间体的一氧化碳来进行的。3)首次以氧化还原酶为电催化剂，实现了二氧化碳选择性电化学还原制甲醇。4)在超细铜修饰的p型硅电极上，二氧化碳的光电还原导致甲烷和乙烯的形成，其电位比铜金属电极上的电位更高。5)利用铜催化剂，开发了甲烷和一氧化碳转化为乙酸的新反应。这提供了甲烷在温和条件下碳-碳键形成反应的第一个例子。少

The Objective of this research project lines in the establishment of chemical transformaitons using small inert molecules such as dinitrogen and methane which are abundant on earth, and carbon dioxide, the increase of which in the atmosphere arises from the use of fossil fuel by the human being and is becoming a serious environmental problems on a global scale. This is the fundamental and basic research towards the development of ideal chemical processes using carbon dioxide and methane as the simple carbon resourse and dinitrogen as the simple nitrogen resource to synthesize valuable organic compounds.Efficient activation and chemical utilization of these small inert molecules are one of the most challenging subjects in chemistry. The main achievements in this project are described below.1) The coordinated dinitrogen in molybdenum and tungsten phosphine complexes has been converted into nitrogen-heterocyclic compounds such as pyrrole and aminopyrrole via a series of reactions under mi … More ld conditions. Indole derivatives have also been synthesized from dinitrogen by using titanium systems. These results will open a new chemistry of nitrogen fixation where a variety of organo-nitrogen compounds are directly prepared from molecular nitrogen.2) Electrochemical reduction of carbon dioxide on a copper electrode gives rise to the formation of methane, ethane, and ethanol. The reaction has been revealed to proceed through the formaiton of carbon monoxide as an intermediate on the electrode.3) Selective electrochemical reduction of carbon dioxide to methanol has been for the first time realized by using redox enzymes as electrocatalysts.4) Photoelectrochemical reduction of carbon dioxide on the p-type silicon electrode modified with ultrafine copper particles has led to the formation of methane and ethylene at a more positive potential than on a copper metal electrode.5) New reactions have been developed which transform methane and carbon monoxide into acetic acids by using copper catalyst. This provides the first example of the carbon-carbon bond formation reactions of methane under mild conditions. Less