Journal of Molecular Catalysis A: Chemical Pub Date : 2016-08-12 , DOI: 10.1016/j.molcata.2016.08.013 Evgeny V. Kudrik , Alexander B. Sorokin
Low temperature selective transformation of alkanes to useful products continues to be an important challenge in chemistry and industry. μ-Nitrido diiron phthalocyanines in combination with H2O2 have been recently identified as powerful oxidation catalysts for these challenging reactions due to the formation of ultra-high valent diiron oxo species PcFe(IV)μNFe(IV)O(Pc+). This very strong two-electron oxidizing species is generated from peroxo complex PcFe(IV)μNFe(III)OOR(Pc) (RH in the case of H2O2) via heterolytic OO bond cleavage. Therein we show that the evolution of the peroxo diiron complex depends on the peroxide structure. Using tBuOOH we have demonstrated the formation of an one-electron oxidizing PcFe(IV)μNFe(IV)O(Pc) and tBuO radical via homolytic OO cleavage of the peroxocomplex. The reactivity of the μ-nitrido diiron tetra-t-butylphthalocyanine − tBuOOH catalytic system was investigated in the oxidation of different CH bonds in alkanes, olefins, aromatic and alkylaromatic compounds. The main products of cyclohexane oxidation were cyclohexanone and cyclohexanol whereas bicyclohexyl was formed in minor amounts even in the presence of O2 and tBuOOH. Under optimal conditions, the turnover numbers of almost 5300 have been achieved.
中文翻译:
μ-nitrido二铁酞菁催化t -BuOOH氧化脂肪族和芳香族CH键
将烷烃低温选择性转化为有用的产品仍然是化学和工业中的重要挑战。由于超高价二价铁氧体物种PcFe(IV)μNFe(IV)O(Pc +)的形成,近来已将μ-Nitrido二铁酞菁与H 2 O 2结合用作强力氧化催化剂。这种非常强的两电子氧化物质是由过氧配合物PcFe(IV)μNFe(III)O O R(Pc)(在H 2 O 2的情况下为R H )通过杂化O生成的。O键裂解。其中我们表明,过氧二铁配合物的演变取决于过氧化物的结构。使用t BuOOH,我们证明了通过过氧配合物的O O均裂,形成单电子氧化的PcFe(IV)μNFe(IV)O(Pc)和t BuO自由基。μ-氮基的反应性二铁四吨-butylphthalocyanine -吨BuOOH催化系统在不同的C的氧化进行了研究烷烃,烯烃,芳族和烷基芳族化合物中的H键。环己烷氧化的主要产物是环己酮和环己醇,而即使在O 2和t BuOOH存在的情况下,也会少量形成双环己基。在最佳条件下,营业额达到了近5300。