权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

New Development of Dioxygenase Model Complexes Complexes for Organic Synthesis

双加氧酶模型配合物的新进展有机合成配合物

基本信息

批准号：
60550607
负责人：
NISHINAGA Akira
金额：
$ 1.41万
依托单位：
Osaka Institute of Technology (1987)Kyoto University (1985-1986)
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1985
资助国家：
日本
起止时间：
1985 至 1987
项目状态：
已结题

项目摘要

Cobalt(II) Schiff base complexes, Co(II)(SB),which show dioxygenase-like activities in aprotic solvents, have been found to catalyze also monooxygenation and dehydrogenation depending on the nature of reaction medium,reaction temperature, substrate,and structure of the cobalt catalyst. In dioxygenation reactions,it has been demonstrated that the ortho regioselectivity observed in the dioxygn incorporation into phenolate substrates is accomplished only when no phenoxy radical intermediate is involved in the dioxygen incorporation step. Coordinately saturated (HO)Co(III)(SB) have been found to promote the oxygenation of aliphatic nitro compounds to corresponding carbonyl products, providing an additional example fpr the dioxygenase-type reactions. On the other hand, it has been found that coordinately unsaturated (HO)Co(III)(SB) lead to monooxygenation reactions. For example, the oxygenations of aromatic hydrazones and aliphatic nitro compounds in methanol result in the oxidative C-C bon … More d cleavage to give carboxylic acid methyl esters, providing new oxidation reactions. Furthermore, styrenes are oxidized in alcohols at 60 ゜C to give acetophenones and l-phenylethanols. The oxygenation of styrene with coordinately unsaturated nonplanar (HO)Co(III)(SB) in 2-propanol results in predominantly formation of l-phenylethanol, in this case the use of optically active complexes leads to the asymmetric induction in the alcohol product. Newly developed synthetically useful dehydrogenation rections using Co(SB) include (1) the oxygenation of aromatic hydrazones to diazo copounds using coordinately saturated (HO)Co(III)(SB) in acetonitrile, (2) the oxygenation of aliphatic hydrazones to l-alkenylcobalt complexes using coordinately unsaturated (HO)Co(III)(SB) in dichloromethane, and (3) the oxidation of alcohols to carbonyl compounds with t-BuOOH in the presence of coordinately saturated (HO)Co(III)(SB). As mentioned above, hydroxo complexes (HO)Co(III)(SB) play important roles in the oxidation reactions. The possibility that (HO)Co(III)(SB) may display superacid and superbase catalyses is also suggested by some preliminary experiments, which will be further investigated. Less

钴(II)席夫碱配合物Co(II)(Sb)在非质子溶剂中表现出类似双加氧酶的活性，根据反应介质的性质、反应温度、底物和钴催化剂的结构，它也可以催化单氧合和脱氢。在双氧合反应中，研究表明，只有在双氧基结合步骤中不涉及苯氧基中间体时，才能实现双氧基与酚类底物的邻位选择性。已发现配位饱和的(Ho)Co(III)(Sb)促进脂肪族硝基化合物氧化成相应的羰基产物，为双加氧酶类型的反应提供了另一个例子。另一方面，已发现配位不饱和(Ho)Co(III)(Sb)导致单氧反应。例如，芳香肼和脂肪族硝基化合物在甲醇中的氧化反应会导致C-C键…的氧化更多的d裂解得到羧酸甲酯，提供新的氧化反应。此外，在60゜C的醇中，苯乙烯被氧化成苯乙酮和L苯乙醇。在异丙醇中，苯乙烯与配位不饱和(Ho)钴(III)(Sb)氧化生成L苯乙醇，在这种情况下，光学活性络合物的使用导致了乙醇产物的不对称诱导。新开发的有用的Co(Sb)脱氢反应包括：(1)在乙腈中用配位饱和(HO)Co(III)(Sb)将芳香肼氧化成重氮钴；(2)在二氯甲烷中用配位不饱和(HO)Co(III)(Sb)将脂肪肼氧化成L-烯基钴配合物；(3)在配位饱和(HO)Co(III)(Sb)存在下，t-BuOOH将醇氧化成羰基化合物。如上所述，羟基配合物(Ho)Co(III)(Sb)在氧化反应中起着重要的作用。初步实验表明，(Ho)Co(III)(Sb)可能具有超强酸和超碱催化作用，有待进一步研究。较少