2,3-二羧基-双环[2.2.1]2,5-庚二烯价键异构化反应的研究

以聚四苯基卟啉(P-TPP)为敏化剂,研究了2,3-二羧基-双环2.2.1]-2,5-庚二烯(N)的光化学价键异构化反应,在0.1mol/L的碳酸钠甲醇溶剂中,在适量的P-TPP存在下,可见光照射时,N可以定量地转化为2,3-二羧基四环2.2.1.0^2,6.0^3,5]庚烷(Q),Q在聚四苯基卟啉钴络合物(Co-P-TPP)催化剂的作用下,又可定量地异构化返回N.分别研究了敏化剂和催化剂用量对反应的影响。通过反应物之间激发态能量的比较及N对P-TPP荧光的猝灭试验,证明光异构化反应是通过电子转移反应机制进行的。

STUDY ON PHOTOCHEMICAL VALENCE ISOMERIZATION OF BICYCLO-[2.2.1]-2,3-DICARBOXY-2, 5-HEPTADIENE

Photochemical valence isomerization of bicyclo 2. 2. 1] -2, 3 -dicarboxy -2, 5 -heptadiene (N) to quadrocyclo2.2.1.0^2,3. 0^5,6]-2, 3 - dicarboxy heptane (Q) was performed by using polytetraphenyl-porphrine(P-TPP)as sensitizer. In addition, The Q can be easily converted into N under the presence of catalyst, Cobalt (Ⅱ) polytetraphenylpor-phrine (Co-P-TPP). The effects of the sensitizer and the catalyst on these isomerization reaction were tested. The comparation between the excited state energy of P - TPP and N indicated that photochemical valence isomerization may go by way of electron transfer from P-TPP to N. The support for the electron transfer machenism is fluorescence quenching of P-TPP by N.