Enhancing the Photochemical Stability of <i>N</i>,<i>C</i>-Chelate Boryl Compounds: C−C Bond Formation versus C═C Bond <i>cis,trans</i>-Isomerization
作者:Chul Baik、Zachary M. Hudson、Hazem Amarne、Suning Wang
DOI:10.1021/ja906430s
日期:2009.10.14
undergoing cis-trans isomerization exclusively upon exposure to UV light. Experimental and TD-DFT computational results establish that the presence of the olefinic bond in B1-B3 provides an alternate energy dissipation pathway for the B(ppy)Mes(2) chromophore, stabilizing the molecule toward photochromic switching via cis-trans isomerization. Furthermore, the incorporation of a cis-trans isomerization pathway
N,C-螯合硼化合物,例如 B(ppy)Mes(2)(ppy = 2-苯基吡啶基,Mes = mesityl)最近已被证明在用紫外线照射时会发生简单且可逆的 CC/CB 键重排,淬灭样品的发射并限制它们在光电器件中的使用。为了解决这个问题,已经合成了四种分子,其中使用乙烯基或乙炔接头扩展了 pi 共轭。这些化合物, (ph-C[三键]C-ppy)BMes(2) (B1A), (ph-CH=CH-ppy)BMes(2) (B1), [p-bis(ppy-CH=CH )苯](BMes(2))(2) (B2) 和 [1,3,5-tris(ppy-CH=CH)苯](BMes(2))(3) (B3) 已被完全表征通过核磁共振和单晶 X 射线衍射分析。所有四种化合物均呈淡黄色,并在紫外线照射下发出蓝色或蓝绿色光。已发现乙炔化合物 B1A 表现出与母体发色团 B(ppy)Mes(2) 相同的光化学不稳定