近年來本實驗室發現由一分子的芳香化合物38及兩分子的間式炔類35於醋酸鈀及醋酸銀的存在下可合成多取代萘37。芳香環化合物提供基本苯環架構，經由連續兩次的碳氫鍵活化來建造萘環結構，據我們所知，這是目前第一個連續經由兩個苯基碳氫鍵活化的方法來製備萘環化合物的例子。數種過渡金屬的催化效能、不同極性的溶劑及氧化劑等添加物對本反應所造成的影響已被檢測，反應已調至最佳化。依據此簡單的合成方法，數種多取代萘環衍生物已被製備，多取代萘化合物38官能基的性質及取代位置，會影響反應性高低及產物位向選擇性。產物5-正丁基-8-甲基-1,2,3,4-四苯基萘(37ea)，5,8-雙異丙基-1,2,3,4-四苯基萘 (37ga)及5,8-雙甲基-1,2,3,4-四(4-甲苯基)萘(37ac)的晶體結構已被分析及測試，其萘環結構的扭曲程度除了與多取代官能基的立體障礙有關以外，CH3π作用也是使萘環結構扭曲的原因之ㄧ。

Recently we found several highly substituted naphthalenes 37 have been synthesized in one pot by treatment of arenes 38 with alkynes 35 in the presence of palladium acetate and silver acetate.
In this Pd-catalyzed protocol, an arene provides a "benzo" unit to construct a naphthalene core via a two-fold aryl CH bond activation. To the best of our knowledge, this is the first example of preparation of naphthalenes from two-fold of aryl CH bond activations. We have optimized the reaction conditions and tested various arenes from the preparation of such molecules. This synthetic method provides three advantages: simple, clean and atomic economic.
Crystal structures of cycloadducts 5-n-butyl-8-methyl-1,2,3,4-tetraphenylnapht-
halene (37ea), 5,8-diisopropyl-1,2,3,4-tetraphenyl-naphthalene (37ga) and 5,8-dimethyl-1,2,3,4-tetra(4-tolyl)naphthalene (37ac) have been analyzed by X-ray diffractions. The twisted structure of naphthalenes arises not only from the over-crowded substituents but also from the contribution of the CH3π interaction.

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