Photocoupling Reactions of Haloaromatic Hydrocarbons With Aromatic Compounds——Synthesis and Mechanism

An effective method of synthesizing polyaromatic hydrocarbons with high selectivity was developed through our research work on the photocoupling reactions between several haloaromatic hydrocarbons and aromatic compounds. The structures of polyaromatic hydrocarbons synthesized were determined by IR, UV, ~1H NMR, MS and elemental analysis, and the crystal structure of 3-(1-naphthyl)-coumarin was established by an crystallographic analysis. Further study of the regioselectivity, orientational effect of substituents, solvent effect, sensitizing and quenching effect supported the proposed mechanism of this type of reaction involving election transfer process under excited triplet state.     

香豆素晶体的光二聚——基态非局部化学控制反应的首例

香豆素及其衍生物有重要的生理活性,对此早期已开展了详尽的研究^[1],对它的光化学性能也有些报道^[2-3]。随着实验手段及检测仪器的进步,不断发现有关香豆素光化学的一些新现象和实验结果,并不断修正过去的报道。Hammond等^[4]报道香豆素在极性溶剂中(乙醇等),直接光解,生成syn-cis二聚体,在非极性溶剂中,未发现二聚体。     

卤代芳烃与芳香化合物的光交联反应——合成与机理

通过研究多种囟代芳烃与芳香化合物的光交联反应,总结出一种高选择性地合成联多芳香化合物的有效方法。同时合成了多种联多芳香化合物并以IR,~1HNMR,MS和元素分析数据确定了它们的结构。其中交联产物3-(1-萘基)香豆素的晶体结构由X射线四圆衍射法解出。进一步研究反应的位置选择性、取代基定位效应、溶剂效应、敏化与猝灭效应等,证明了激发三线态下按电子转移的反应机理。