1,3-二联苯基-2,4-二吡啶基环丁烷的结构与光化学性质(英文)  

Crystal Structure and Photochemical Properties of r-1,c-2,t-3,t-4-1,3-bis(4-biphenyl)-2,4-di(4-pyridyl)cyclobutane

作　　者：张文勤[1] 张志明[1] 郑艳[1] 王淑丽[1] 赵抒娜[1] 

机构地区：[1]天津大学化学系,天津300072

出　　处：《物理化学学报》2000年第3期207-213,共7页Acta Physico-Chimica Sinica

基　　金：国家自然科学基金!资助项目 (29602006)

摘　　要：通过反 1 (4 联苯基) 2 (4 吡啶基)乙烯(E I)在稀硫酸中的光二聚反应合成了r 1,c 2,t 3,t 4 1,3 双(4 联苯基) 2,4 二(4 吡啶基)环丁烷(II).用X射线衍射法测定了其结构.晶体II为单斜晶系,空间群为P21/n,晶胞参数:a=1.0038(2),b=1.8995(4),c=1.4647(3)nm,β=98.82(3)°,晶胞内分子数为4.在II的分子中,其四元环呈蝶式构象.研究发现,在短波紫外光照射下,II容易发生光解开环反应生成其反式单体E I,随后新生成的E I经反顺异构化反应转变为其顺式异构体(Z I),最后反顺异构化反应达到平衡.光解II或E I得到同样的反顺异构体混合物.r-1,c-2, t-3, t-4-1,3-bis(4-biphenyl)-2,4-di(4-pyridyl)cyclobutane (II) was obtained in diluted sulfuric acid by photodimerization reaction.Its structure was determined by X-ray diffraction method.The crystal is monoclinic,space group is P21/n,with a=1.0038(2),b=1.8995(4),c=1.4647(3)nm,β=98.82(3)°,Z=4. The cyclobutane ring of II has puckered conformation.It was found that under short wave UV light II is easy to be photolyzed to reproduce its monomer trans-1-(4-biphenyl)-2-(4-pyridyl)ethene (E-I),and then the new formed E-I transforms to its cis-isomer(Z-I) through trans-cis isomerization.Finally,the equilibrium of isomerization establishes between E-I and Z-I.Photolysis of II or E-I will form the same isomerization mixture.

关 键 词：晶体结构 光化学性质 联苯基 吡啶基 环丁烷 

分 类 号：O624[理学—有机化学]