Ferreira Marli, Girotto Edivandro, Bentaleb Ahmed, Hillard Elizabeth A, Gallardo Hugo, Durola Fabien, Bock Harald
Centre de Recherche Paul Pascal, Centre National de la Recherche Scientifique and Université de Bordeaux, 115 avenue Schweitzer, 33600 Pessac (France), Fax: (+33) 556845600; Departamento de Química, Universidade Federal de Santa Catarina, 88040-900 Florianópolis, SC (Brazil).
Chemistry. 2015 Mar 9;21(11):4391-7. doi: 10.1002/chem.201406172. Epub 2015 Feb 5.
Although the double Friedel-Crafts acylation of arenes with ethyl chloroglyoxylate is hindered by the strongly deactivating effect of the first-entering glyoxylic substituent, the double reaction is successful with the reactive arene perylene under long reaction times and with concomitant ester hydrolysis. The reaction is regiospecific, giving the 3,9-regioisomer exclusively. This perylenylenediglyoxylic acid is condensed first with o-bromophenylacetic acid and then with α-branched alkylamines to yield the title compounds. Whilst the corresponding tetraalkyl esters only show monotropic mesophases, these diimides show enantiotropic columnar mesophases that can be maintained at room temperature if racemically branched alkyl chains of moderate size are used. A palladium-induced C-C bond migration during the build-up of the arene system leads to an isomeric side product of reduced symmetry that can be isolated by aggregation-controlled chromatographic separation. The HOMO and LUMO energies of the title compounds are considerably higher than those of established perylenetetracarboxdiimides.
尽管芳烃与氯乙醛酸乙酯的双傅克酰基化反应会受到首先引入的乙醛酸取代基的强烈钝化作用的阻碍，但在长时间反应并伴随酯水解的情况下，该双反应对于活性芳烃苝是成功的。该反应具有区域选择性，仅生成3,9-区域异构体。这种苝二乙醛酸首先与邻溴苯乙酸缩合，然后与α-支链烷基胺反应生成标题化合物。虽然相应的四烷基酯仅显示单变介晶相，但这些二酰亚胺显示出对映柱状介晶相，如果使用中等大小的外消旋支链烷基链，则可以在室温下保持。在芳烃体系构建过程中，钯诱导的C-C键迁移会导致对称性降低的异构体副产物，该副产物可通过聚集控制色谱分离进行分离。标题化合物的最高占据分子轨道（HOMO）和最低未占据分子轨道（LUMO）能量明显高于已有的苝四羧酸二酰亚胺。
