Biomimetic Chemistry of Oxygen and Nitrogen Monoxide

1.模型加氧酶复合物催化活性的现场控制。在苯酚的仿生氧合反应中，在配位有机碱存在的情况下，模型加氧酶复合物促进了苯氧自由基中间体和超氧金属配合物之间的反应。模型加氧酶配合物还能催化2-氨基酚的氧脱氢，导致2-氨基苯恶嗪-3-酮的高选择性生成，其中由2-亚氨基醌和催化剂组成的二元配合物中间体在ESR研究中起着重要作用。模型加氧酶配合物的活性组分通过Michael反应和醛醇反应催化碳-碳键的形成，以及由催化剂结构控制的高区域选择性溶剂裂解环氧化物。这些催化反应是由活性物质的场控超酸碱催化作用引起的。这些结果为仿生化学研究提供了有趣的信息。超氧钴（III）配合物的化学反应性。研究发现，配位不饱和的超氧钴（III）配合物在硼氢化钠存在下催化乙烯的氧化作用，导致选择性生成1-苯乙醇，而配位饱和的超氧钴（III）配合物选择性地将亚硝基苯氧化为硝基苯。ESR研究表明，亚硝基化合物的氧化涉及到超氧基团对亚硝基的自由基加成。目前研究了超氧钴（III）与一氧化氮配合物和混合金属多过氧配合物的化学性质。

1.Field Control of Catalytic Activity of Model Oxygenase Complex. In biomimetic oxygenations of phenols, the reaction between a phenoxy radical intermediate and a superoxometal complex is promoted by model oxygenase complexes in the presence of a coordinative organic base. The model oxygenase complxes also catalyze the dehydrogenation of 2-aminophenols by oxygen leading to highly selective formation of 2-aminophenoxazin-3-ones, where a binary complex intermediate comprised of 2-iminoquinone and catalyst plays an important role as judged by ESR studies. It has also been found that the active species of the model oxygenase complexes catalyze carbon-carbon bond formation by Michael and aldol reactions, and highly regioselective solvoltic cleavage of epoxides controlled by the structure of the catalyst as well. These catalytic reactions are caused by field controlled super acid-base catalysis of the active species. These results provide interesting information in the biomimetic chemistry.2. Chemical Reactivity of Superoxocobalt (III) Complexes. It is found that coordinately unsaturated superoxocobalt (III) complexes catalyze the oxygenation of stirenes in the presence of sodium borohydride leading to the selective formation of 1-phenylethanols, whereas a coordinately saturated superoxocobalt (III) complex oxidizes nitrosobenzenes to nitrobenzenes selectively. ESR studies show that the oxidation of nitroso compounds involves radical addition of the superoxo species to the nitroso group.The chemistry of superoxocobalt (III) complexes with nitrogen monoxide and of mixed metal mu-peroxo complexes is currently investigated.