Expanding the Registry of Aromatic Amide Foldamers: Folding, Photochemistry and Assembly Using Diaza-anthracene Units

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• 作者：Emanuela Berni ; Christel Dolain ; Brice Kauffmann ; Jean-Michel Lé ; ger ; Chuanlang Zhan ; Ivan Huc
• 刊名：Journal of Organic Chemistry
• 出版年：2008
• 出版时间：April 4, 2008
• 年：2008
• 卷：73
• 期：7
• 页码：2687 - 2694
• 全文大小：471K
• 年卷期：v.73,no.7(April 4, 2008)
• ISSN：1520-6904

文摘

The synthesis of various 1,8-diaza-4,5-dialkoxy-2,7-anthracene dicarboxylic acid derivatives and theirincorporation into cyclic and helically folded aromatic oligoamides are reported. The ability of the diaza-anthracene monomers to undergo photoaddition or head-to-tail photodimerization was investigated inthe solid state and in solution. Quantitative conversion of a monomer diester to the corresponding head-to-tail photodimer could be achieved in the solid state without protection from oxygen. The formation ofan emissive excimer between two diaza-anthracene units appended at the end of a helically folded oligomerwas demonstrated. Intramolecular photodimerization was not observed in this compound, possibly dueto the low thermal stability of the head-to-head photoadduct. A cyclic oligoamide composed of twodiaza-anthracene and two pyridine units was shown to adopt a flat conformation and to form columnarstacks in the solid state. Longer, noncyclic oligoamides composed of one or two diaza-anthracene unitswere shown to adopt helical conformations that exist preferentially as double helical dimers.