Aerobic Oxidative Coupling of Amines by Carbon Nitride Photocatalysis with Visible Light
Aerobic Oxidative Coupling of Amines by Carbon Nitride Photocatalysis with Visible Light
复制标题
可见光氮化碳光催化胺的有氧氧化偶联
DOI：
10.1002/anie.201004365
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发表时间：
2011-01-01
影响因子：
16.6
通讯作者：
Blechert, Siegfried
中科院分区：
文献类型：
--
作者：
Su, Fangzheng;Mathew, Smitha C.;Blechert, Siegfried
利用太阳光作为化学反应的驱动力在合成化学中显示出巨大的前景。[1]由于大多数有机分子在可见光谱中是透明的，因此光敏剂通常用于通过猝灭剂介导的电子转移来引发有机转化。[2]金属有机染料由于其激发态的长寿命而被用作这样的敏化剂;然而，存在对染料在长期操作期间的稳定性的担忧。[3]近年来，本课题组在可见光下合成了一种新型的无金属光催化剂--石墨氮化碳（gC3N4）。[4]因此，进行了电化学和光学分析，以揭示gC 3 N4的价带顶部和导带底部。这些条带在1.4V和1.5V下检测到。3V相对于正常氢电极。[5]光生电子具有较大的还原电位，可以很容易地激活分子氧介导能量和电子转移，而空穴的中等氧化电位防止合成的有机化合物被氧化在一个不可控的方式。这表明gC3N4可以作为一种温和的光催化剂，在更广泛的方式促进有机氧化还原合成。事实上，当我们的工作扩展到选择性醇氧化时，发现光激发的gC3N4可以激活
The use of sunlight as a driving force for chemical reactions shows great promise in synthetic chemistry.[1] As most organic molecules are transparent in the visible spectrum, light sensitizers are often employed to trigger organic transformations through electron transfer mediated by quenching reagents.[2] Metal–organic dyes have been used as such sensitizers because of the long lifetime of their excited states; however, there is a concern about the stability of dyes during long-term operations.[3] The inclusion of precious metals such as ruthenium in the dyes also restricts their practical applications.Recently, our research group has introduced graphitic carbon nitride (gC 3N4) as a metal-free photocatalyst for hydrogen evolution using visible light.[4] Electrochemical and optical analyses have been therefore performed to reveal the top of the valance band and the bottom of the conduction band of gC 3N4. These bands were detected at 1.4 V and À1. 3 V versus the normal hydrogen electrode, respectively.[5] Light-induced electrons with large reduction potential can easily activate molecular oxygen to mediate energy and electron transfer while the moderate oxidation potential of the holes prevents the synthesized organic compounds from being oxidized in an uncontrollable manner. This feature suggested that gC 3N4 can act as a gentle photocatalyst for promoting organic redox synthesis in a broader fashion. Indeed, when our work was extended to selective alcohol oxidation, it was found that light-excited gC 3N4 can activate