【作者】 张彦英；

【导师】 徐龙鹤；

【作者基本信息】 大连理工大学 ， 应用化学， 2003， 博士

【摘要】 本论文利用钯催化反应设计合成了五个系列结构新颖的3-和7-位共轭延长的香豆素类化合物，化合物的结构通过红外光谱（IR）、核磁共振谱（NMR）、元素分析（EA）、高分辨质谱（HRMS）和X-四圆衍射仪等测试手段进行了表征。测试了所有合成香豆素化合物的紫外可见光谱、荧光光谱以及荧光量子效率，并研究了这些香豆素荧光化合物的结构与光谱性能之间的关系。 采用Heck反应以醋酸钯（Pd（OAc）₂）为催化剂，三邻甲氧基苯基膦为配体，DMF做溶剂，合成了八个新型3-二苯乙烯基取代香豆素化合物。其中3-位二苯乙烯基取代的香豆素化合物与开链的二苯乙烯化合物相比，形成香豆素环后化合物吸收波长变化不大，但荧光发射波长有较大红位移，荧光量子效率有很大提高。晶体结构数据表明3-（4′-氯二苯乙烯-4-基）香豆素为反式二苯乙烯结构，香豆素环与直接相连的苯环形成二面角为42.66°，而与二苯乙烯另一端的苯环近乎呈一个平面。对于7-位引入二乙氨基取代的系列化合物光谱性能研究表明，3-（4′-氯二苯乙烯-4-基）-7-二乙氨基香豆素化合物具有较高的荧光量子效率。 采用Sonogashira反应以二三苯基膦二氯化钯（Pd（PPh₃）₂Cl₂）为催化剂合成了四个3-位二苯乙炔共轭延长的香豆素化合物。与对应的3-位二苯乙烯基取代香豆素化合物相比，3-位二苯乙炔基取代的香豆素最大吸收波长和荧光发射波长均发生明显蓝位移，而且荧光量子效率较低。当7-位引入二乙氨基时，虽然最大吸收波长和荧光发射波长均相差不大，但3-位二苯乙炔基取代的香豆素却具有较高的荧光量子效率，这是由于圆筒状对称的三键有利于电子在线性共轭结构进行有效的传递。 同样以钯催化的Sonogashira反应较高收率地合成了四个未见文献报道的新型烷炔取代香豆素化合物。随后利用生成的香豆素端炔化合物和邻碘苯酚进行钯催化的加成环合反应，较高收率地合成了两个2-苯并呋喃取代的香豆素化合物。光谱性能研究表明，对呋喃固环的2-苯并呋喃取代香豆素化合物来说，当香豆素环7-位上无取代基时化合物的荧光量子效率较低，但7-位上引入供电的二乙氨基时化合物荧光量子效率较高。 采用钯催化香豆素重氮盐的Heck反应合成了七个7-位苯乙烯基取代香豆素化合物，该方法反应条件温和且收率较高。通过光谱性能的研究，发现苯乙烯对位取代基中除强供电的二乙氨基（-NEt₂）对化合物的最大吸收波长影响较大 摘要外，弱供电基毛H3和吸电基^CN对最大吸收波长影响都不大，该类化合物荧光发射波长普遍发生红位移，且随着取代基供电效应的增大而增大。就化合物的荧光量子效率而言，对甲基和对氰基取代的苯乙烯香豆素化合物相对较高。 在把催化下通过4-甲基一7一碘香豆素和苯乙炔的偶联反应制备了7一位苯乙炔基取代香豆素化合物。.与7一位苯乙烯香豆素化合物相比，该类化合物的最大吸收波长和荧光发射波长都不同程度地发生蓝移，除供电的二乙氨基取代的苯乙炔化合物的荧光量子效率明显高于对应的苯乙烯取代化合物外，其它化合物的荧光量子效率变化不大。与在THF中呈蓝色荧光的4一甲基一7一二乙氨基香豆素相比，二乙氨基取代苯乙炔及苯乙烯化合物在THF中均呈黄色荧光。更多还原

【Abstract】 Five series of novel coumarins were synthesized by palladium-catalyzed reaction and the structures were characterized by IR, NMR, EA, MS and X-ray diffraction. The absorption-emission spectra and fluorescence quantum yields were determined and the relationships between molecular structure and fluorescence properties were also studied.3-Stilbenylcoumarins were synthesized by Pd(OAc)2-catalyzed Heck reactionusing TOP as ligand in DMF. Determination of 3-(4’-chlorostilben-4-yl)coumarin’s single crystal by X-ray diffraction showed that the newly formed olefin was a trans structure and that the hedral angle between the coumarin skeleton and near benzene ring of the stilbene was 42.66 , but that the coumarin skeleton and the far benzene ring were on almost the same plane. Compared to its open-chain analog, 3-(4’-chlorostilben-4-yl)coumarin rigidified by lactone produced a considerably enhanced fluorescence quantum yield and a large bathochromic shift in the emission maximum but little change in absorption. Study of the 7-diethylamino-3-stilbenylcoumarin series prepared in this paper showed that 4’-Cl-substituted stilbenylcoumarin had a higher fluorescence quantum yield than the others in that series.Four 3-diphenylacetylenylcoumarins were prepared by Pd(PPli3)2Cl2-catalyzed Sonogashira reaction. Compared with their corresponding 3-stilbenylcoumarins, they had blue shifts in the absorption and emission spectra and lower fluorescence quantum yields. With the introduction of electron donor (-NEta) at the 7-position of any of these compounds, there was only a slight difference in the absorption and emission maxima of these 7-NEt2-substituted coumarins. However, the diphenylacetylene-extended 7-NEt2-substituted coumarin did have a higher fluorescence quantum yield, which may be attributed to the efficient electronic communication of the structure’s triple-bond cylindrical symmetry.Four alkylacetylenyl-substituted coumarins were synthesized by palladium-catalyzed Sonogashira reaction and two 2-benzofuran-substitutedcoumarins were synthesized by palladium-catalyzed cycloaddition of 2-iodophenoland terminal acetylenylcoumarin in relatively high yields. Study of the spectra characteristics showed that 2-benzofuran-substituted coumarin without any substituent at the 7-position had a low fluorescence quantum yield, but that with the introduction of the electron-donating diethylamino at its 7-position, the fluorescence quantum yield increased considerably.Seven 7-styrylcoumarins were synthesized by palladium-catalyzed Heck reaction of coumarin diazonium salts with substituted styrenes. These reactions yielded well under mild conditions. Introducing a strong electron donor (-NEt2) at the p-position of 7-styrene caused a significant bathochromic shift of the absorption maximum, while a weak electron-donor (-CHa) or an electron-acceptor (-CN) produced little change. Bathochromic shifts of the emission maxima also occurred and increased with the enhancement of the substituent’s electron-donating ability. The p-CH3 and p-CN substituted styrylcoumarins had higher fluorescence quantum yields than the other styrylcoumarins.7-Phenylacetylenylcoumarins prepared from 4-methyl-7-iodocoumarin and substituted phenylacetylene by Pd-catalyzed reaction had similar fluorescence quantum yields as the corresponding 7-styrylcoumarins, with blue shifts in absorption and emission maxima, except that strong electron-donating diethylamino substituted 7-phenylacetylenylcoumarin had a higher fluorescence quantum yield than the corresponding 7-styrylcoumarin and they both produced yellow fluorescence in THF in contrast to the blue fluorescence produced by 4-methyl-7-diethylamino coumarin in THF.更多还原