Department of Chemistry, Kansas State University, Manhattan, Kansas 66506-0401, USA.
J Am Chem Soc. 2010 Dec 15;132(49):17635-41. doi: 10.1021/ja1088309. Epub 2010 Nov 22.
Cycloiptycenes are elusive and synthetically challenging molecules. We report the first synthesis of two substituted cyclododeciptycene tetraquinones via a sequence of intermolecular and intramolecular Diels-Alder reactions from cis,cis-heptiptycene tetraquinone 2 and substituted 7,16-dihydro-7,16-(o-benzeno)heptacenes 3. Heptiptycene tetraquinone 2 was made from triptycene bisquinone 4 and 1,4-dimethoxyanthracene in three steps, and 6,8,15,17-tetramethoxy-7,16-dihydro-7,16-(o-benzeno)heptacene (3a) was synthesized from triptycene bisquinone 4 and 1,4-dihydro-2,3-benzoxathiin-3-oxide in four steps. The structure of a cyclododeciptycene, 1a, was determined by a single-crystal X-ray analysis. The synthetic sequence is general and should allow the incorporation of various alkoxy and acetoxy substituents appended to the cycloiptycene framework.
环癸并四元烯是难以捉摸且具有挑战性的合成分子。我们报告了首例通过分子间和分子内 Diels-Alder 反应，从顺式，顺式-庚四烯四醌 2 和取代的 7,16-二氢-7,16-(o-苯并)庚三烯 3 合成两个取代的环十二并四元烯四醌。庚四烯四醌 2 由三并苯双醌 4 和 1,4-二甲氧基蒽合成三步，6,8,15,17-四甲氧基-7,16-二氢-7,16-(o-苯并)庚三烯（3a）由三并苯双醌 4 和 1,4-二氢-2,3-苯并恶嗪-3-氧化物合成四步。通过单晶 X 射线分析确定了环十二并四元烯 1a 的结构。该合成序列具有通用性，应允许在环癸并四元烯骨架上引入各种烷氧基和乙酰氧基取代基。
