Exploitation of P-450 Type Catalytic Oxidations and their Application to Organic Synthesis

本研究项目的主要目的是获得非活性有机底物仿生氧化转化的创新方法，并将其推广到有机合成和工业过程中。基于过渡金属催化剂模拟细胞色素P-450单加氧酶的新策略，从合成的角度研究了过渡金属中各种氧金属物种的生成、反应活性和催化作用。由低价Ru络合物和过氧化物如t-BuOOH和AcOOH生成的氧钚物种已被证明是未反应底物氧化的高活性催化物种。因此，具有过氧物的Ru催化剂可以对胺、酰胺、酚和烷烃进行各种特定的氧化反应。这些新反应为非反应底物的转化提供了一种有效的合成方法，包括氨基烯烃的仿生环化反应、胺的α取代反应以及由苯酚合成苯二酚的反应。氧金属物种生成原理的延伸导致了在醛存在下的新型有氧氧化反应。在低价过渡金属催化剂和醛的存在下，在温和的条件下，烷烃的有氧氧化可以有效地进行。随着对工业上重要的环己烷氧化的进一步研究，以CuCl2冠醚或Ru氟化的卟啉Ru络合物为催化剂，取得了极高的效率和选择性。

The main aim of the present research project is to acquire innovative method for biomimetic oxidative transformations of unreactive organic substrates and to extend it to the organic syntheses and industrial processes. Based on the new strategy for simulating enzymatic function of cytochrome P-450 monooxygenases with transition metal catalysts, the generation, reactivity and catalysis of various oxometal species of transition metals have been investigated from synthetic viewpopints. Oxoruthenium species generating from low valent ruthenium complexes and peroxides such as t-BuOOH and AcOOH has proven to be highly reactive catalytic species for the oxidations of unreactive substrates. Thus, a variety of specific oxygenation reactions of amines, amides, phenols and alkanes can be performed with ruthenium catalysts with peroxides. These new reactions provides a powerful synthetic method for transformations of unreactive substrates, including biomimetic cyclization of aminoolefins, alpha-substitution of amines, and quinone synthesis from phenols. Extension of the principle of the generation of oxometal species has led to the novel aerobic oxidations in the presence of aldehydes. Aerobic oxidation of alkanes can be performed efficiently under mild conditions in the presence of a catalytic amount of low valent transition metal catalysts and aldehydes. As a consequence of further study focused on the oxidation of industrially important cyclohexane, extremely high efficiency and selectivity have been achieved using CuCl_2-crown ethers or ruthenium fluorinated porphyrin ruthenium complexes as a catalyst.