Furutani Yuji, Kandori Hideki, Kawano Masaki, Nakabayashi Koji, Yoshizawa Michito, Fujita Makoto
Department of Frontier Materials, Nagoya Institute of Technology, Showa-ku, Nagoya 466-8555, Japan.
J Am Chem Soc. 2009 Apr 8;131(13):4764-8. doi: 10.1021/ja8089075.
In the unusual photooxidation of alkanes within the cavity of a self-assembled M(6)L(4) cage complex (1), the proposed reaction mechanism involves the generation of the host anion radical and guest cation radical via guest-to-host photoinduced electron transfer (PET). In the present study, the postulated host anion radical was elucidated by in situ IR spectroscopy. The difference IR spectrum before and after the irradiation of the clathrate complex 1a [symbol: see text] (2)(4) (2 = adamantane) features a dominant negative peak at approximately 1500 cm(-1), which is attributed to the decrease in the CN stretching vibration and thus indicative of the structural change in the triazine core of the cage. Electrochemical measurements and theoretical calculations show the remarkably great electron-accepting ability of the triazine core. These results strongly support the proposal of guest-to-host PET.
在自组装的M(6)L(4)笼状配合物(1)腔内烷烃的特殊光氧化反应中，提出的反应机理涉及通过客体到主体的光诱导电子转移(PET)生成主体阴离子自由基和客体阳离子自由基。在本研究中，通过原位红外光谱对假定的主体阴离子自由基进行了阐明。笼形配合物1a符号：见正文(4)(2 =金刚烷)辐照前后的红外光谱差异在约1500 cm(-1)处有一个占主导的负峰，这归因于-CN伸缩振动的降低，从而表明笼状结构中三嗪核的结构变化。电化学测量和理论计算表明三嗪核具有非常强的电子接受能力。这些结果有力地支持了客体到主体PET的提议。
