Selective aerobic oxidation of alcohols by a mesoporous graphitic carbon nitride/N-hydroxyphthalimide system under visible-light illumination at room temperature

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• 作者：Pengfei Zhang ; Jiang Deng ; Jianyong Mao ; Haoran Li ; Yong Wang ; ^{chemwy@zju.edu.cn" class="auth_mail" title="E-mail the corresponding author}Author Vitae
• 关键词：Aerobic oxidation ; Benzyl alcohol ; N-hydroxyphthalimide ; Radical ; Carbon nitride
• 刊名：Chinese Journal of Catalysis
• 出版年：2015
• 出版时间：September 2015
• 年：2015
• 卷：36
• 期：9
• 页码：1580-1586
• 全文大小：869 K

文摘

By combination of photocatalysis and organocatalysis, a metal-free system composed of mesoporous graphitic carbon nitride (mpg-C₃N₄) and N-hydroxyphthalimide (NHPI) offers an efficient and environmentally friendly method for the oxidation of alcohols at room temperature. As a wide-band gap semiconductor, mpg-C₃N₄ absorbs visible light and uses the energy to activate NHPI, resulting in high catalytic activity in the subsequent oxidation of alcohols. Interestingly, the main oxidation product of benzyl alcohol can be tuned from benzoic acid to benzaldehyde by increasing the ratio of mpg-C₃N₄ in the catalyst system. To further understand the reaction route, electron spin resonance and Fourier transform infrared measurements were carried out, confirming that active oxygen and phthalimide N-oxyl radicals formed in the mpg-C₃N₄/NHPI system. Based on these results, a catalytic mechanism for the mpg-C₃N₄/NHPI system was proposed. Moreover, this metal-free system also works well for the oxidation of various aromatic alcohols with good selectivity for aldehydes or ketones.