Department of Materials Science and Chemistry, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280, Japan.
Chemistry. 2010 Jan 18;16(3):890-8. doi: 10.1002/chem.200901668.
We synthesized a series of 1,4,7,10-tetraalkyltetracenes using a new 2,6-naphthodiyne precursor and 2,5-dialkylfurans as starting materials (alkyl=methyl to hexyl). Surprisingly, the solid-state color of the tetracenes ranges through yellow, orange, and red. Both yellow and red solids are obtained for the butyl derivative. Optical properties in solution show no marked differences; however, those in the solid state show characteristics that vary with alkyl side-chain length: methyl, propyl, and pentyl derivatives are orange; ethyl and butyl derivatives are yellow; and another butyl and hexyl derivative are red. X-ray analyses reveal that the molecular structures are planar, semi-chair, or chair forms; the chair form takes a herringbone-like arrangement and the other forms take slipped parallel arrangements. The mechanism of crystallochromy is discussed in terms of molecular structure, crystal packing, and calculations that take account of exciton coupling.
我们使用一种新的 2,6-萘二炔前体和 2,5-二烷基呋喃作为起始材料合成了一系列 1,4,7,10-四烷基四并苯（烷基=甲基至己基）。令人惊讶的是，四并苯的固态颜色范围从黄色、橙色到红色。丁基衍生物可得到黄色和红色固体。溶液中的光学性质没有明显差异；然而，在固态下，它们的特征随烷基侧链长度而变化：甲基、丙基和戊基衍生物呈橙色；乙基和丁基衍生物呈黄色；另一个丁基和己基衍生物呈红色。X 射线分析表明，分子结构为平面、半椅式或椅式；椅式呈人字形排列，其他形式呈滑移平行排列。根据分子结构、晶体堆积和考虑激子耦合的计算，讨论了结晶变色的机制。
