Thermal reaction of [3,4]-benzo-8-substituted-3Z,5Z,7E-octatetraenes and quantum-chemical study of the (8π,6π)-electrocyclisation
作者:Irena Škorić、Fabijan Pavošević、Mario Vazdar、Željko Marinić、Marija Šindler-Kulyk、Mirjana Eckert-Maksić、Davor Margetić
DOI:10.1039/c1ob05802a
日期:——
The first example of thermal (8π,6π)-electrocyclisation of 1,3,5,7-octatetraene with one double bond embedded in an aromatic moiety is described. By this process, [3,4]-benzo-8-substituted octatetraene derivatives, the cis,trans-1-(o-vinylphenyl)-4-(R = Me, Ph, 2-furyl)buta-1,3-dienes were transformed to a new endo-7-(R = Me, Ph, 2-furyl) and exo-7-(R = Me)-2,3-benzobicyclo[4.2.0]octa-2,4-dienes. Mechanism
热(8π,6π)-电环化的第一个例子 1,3,5,7-辛烯描述了在芳族部分中嵌有一个双键的化合物。通过该过程,[3,4]-苯并-8-取代的辛酸酯衍生物,即顺式,反式-1-(邻-乙烯基苯基)-4-(R = Me,Ph,2-呋喃基)buta-1,3-二烯被转化为新的内基-7-(R = Me,Ph,2-furyl)和外-7-(R = Me)-2,3-苯并双环[4.2.0] octa-2,4-二烯。还通过DFT量子化学计算研究了反应机理。M06 / 6-311 + G(d,p)// M06 / 6-31 + G(d,p)计算表明,在苯基和2-呋喃基取代基的情况下,单个内异构体的形成取决于exo -6π电环化的活化壁垒比8π-环还原的活化壁垒高。