MONOOXYGENASE-LIKE OXIDATION OF HYDROCARBONS BY H2O2 CATALYZED BY MANGANESE PORPHYRINS AND IMIDAZOLE - SELECTION OF THE BEST CATALYTIC-SYSTEM AND NATURE OF THE ACTIVE OXYGEN SPECIES
MONOOXYGENASE-LIKE OXIDATION OF HYDROCARBONS BY H2O2 CATALYZED BY MANGANESE PORPHYRINS AND IMIDAZOLE - SELECTION OF THE BEST CATALYTIC-SYSTEM AND NATURE OF THE ACTIVE OXYGEN SPECIES
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DOI：
10.1021/ja00233a023
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发表时间：
1988-12-07
影响因子：
15
通讯作者：
MANSUY, D
中科院分区：
文献类型：
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作者：
BATTIONI, P;RENAUD, JP;MANSUY, D
单独的Fe和Mn卟啉几乎不能催化H2 O2环辛烯环氧化或环辛烷羟基化。在咪唑存在下，Mn（III）卟啉，特别是Mn（TDCPP）Cl，是比Fe卟啉更好的氧原子从H2 O2转移到烃类的催化剂。通过对各种Mn卟啉催化剂和氮基助催化剂的研究，选出了Mn（TDCPP）Cl与10-20当量咪唑的最佳体系。该体系导致烯烃环氧化的高产率（在室温下在小于1小时内90-100%）。1，2-二烷基乙烯的环氧化是立体定向的，并且对应于氧原子到双键的顺式加成。该体系还导致各种烷烃如环己烷、环辛烷、金刚烷、四氢萘或四氢化萘被H2 O2氧化，形成相应的醇和酮，产率为40 - 80%。Mn（TDCPP）Cl-咪唑-PhlO和Mn（TDCPP）Cl-咪唑-H2 O2体系表现出以下：（i）对于芪和己-2-烯的环氧化的相同立体特异性，（ii）对于异戊二烯和柠檬烯的环氧化以及正庚烷的羟基化的相同区域选择性，和（iii）对于环己烯和环辛烷和环辛烯的混合物的氧化的几乎相同的化学选择性。这表明，非常相似的，如果不是相同的，高valentMn-氧代中间体是两个系统中的活性氧化物种。因此，由于咪唑的存在，可以通过使用Mn（TDCPP）Cl催化剂和H2 O2代替PhIO作为氧原子供体来进行烃的有效仿生单氧化。
Fe and Mn porphyrins alone are almost unable to catalyze cyclooctene epoxidation or cyclooctane hydroxylation by H202. In the presence of imidazole, Mn (III) porphyrins, and particularlyMn (TDCPP) Cl, are much better catalysts than Fe porphyrins for oxygen-atom transfer from H202to hydrocarbons. From a study of various Mn porphyrin catalysts and nitrogen base cocatalysts, the most efficient system that has been selected involves Mn (TDCPP) Cl in thepresence of 10-20 equiv of imidazole. This system leads to high yields of alkene epoxidation (90-100% in less than 1 h at room temperature). Epoxidation of 1, 2-dialkylethylenes is stereospecific and corresponds to a syn addition of an oxygen atom to the double bond. This systemalso leads to theoxidation by H202 of various alkanes such as cyclohexane, cyclooctane, adamantane, ethylbenzene, or tetralin, with formation of the corresponding alcohols and ketones in yields between 40 and 80%. The Mn (TDCPP) Cl-imidazole-PhlO and Mn (TDCPP) Cl-imidazole-H202 systems exhibit the following:(i) identical stereospecificities for the epoxidation of stilbene and hex-2-ene,(ii) identical regioselectivities for the epoxidation of isoprene and limonene as well as for the hydroxylation of «-heptane, and (iii) almost identical chemoselectivities for the oxidation of cyclohexene and of mixtures of cyclooctane and cyclooctene. This indicates that very similar, if not identical, high-valentMn-oxo intermediates are the active oxygenating species in both systems. Thus, thanks to the presence of imidazole, it is possible to perform efficient biomimetic monooxygenations of hydrocarbons by using the Mn (TDCPP) Cl catalyst and H202 instead of PhIO as the oxygen-atom donor.