A series of (E)-1,2-diaryldigermenes incorporating bulky Eind groups: structural characteristics and absorption properties
A series of (E)-1,2-diaryldigermenes incorporating bulky Eind groups: structural characteristics and absorption properties
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一系列包含庞大 Eind 基团的 (E)-1,2-二芳基二锗烯：结构特征和吸收性能
DOI：
10.1039/d2dt03427a
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发表时间：
2022
影响因子：
4
通讯作者：
Tsukasa Matsuo
中科院分区：
文献类型：
--
作者：
Shogo Yagura;Naoki Hayakawa;Airi Kuroda;Kei Ota;Rhota Tanishita;Genya Urasaki;Tsukasa Nakahodo;Hidetaka Nakai;Manabu Hoshino;Daisuke Hashizume;Tsukasa Matsuo
一系列(E)-1，2-二芳基二氢呋喃，(EIND)ArGeAr(Eind)[Ar=苯基(2)，噻吩基(3)，9，9-二甲基-2-荧基(4)和2，2‘-二硫杂环-5-基(5)]，通过1，2-二溴香烯，(Eind)BrGeBr(Ind)(1)与ArLi反应，得到黄橙红色结晶固体。在2-5的晶体中，晶核表现出一种柔性的反折几何构型，Ge-Ge矢量与CEind-Ge-Car平面之间的反弯角度(θ)分别为34.04(12)°(2)、38.3(3)°和38.8(3)°(3)、33.69(12)°(4)和39.30(13)°(5)。在UV-Vis光谱中观察到较强的π-π*吸收峰，其最大吸收峰位于4 5 1 nm(ε=1.3×10 4)(2)、4 5 5 nm(ε=9.7×10 3)(3)、4 80 nm(ε=1.3×10 4)(4)和4 97 nm(ε=1.4×10 4)(5)，保留了溶液中的Gege双键。吸收数据和密度泛函理论计算证明了Gege生色团和芳香环之间的本征π共轭，包括随着碳π-电子体系的扩展而使HOMO-LUMO禁带(LUMO E)变窄。
A series of (E)-1,2-diaryldigermenes, (Eind)ArGeGeAr(Eind) [Ar = phenyl (2), thiophen-2-yl (3), 9,9-dimethyl-2-fluorenyl (4) and 2,2′-bithiophen-5-yl (5)], supported by the fused-ring bulky 1,1,3,3,5,5,7,7-octaethyl-s-hydrindacen-4-yl (Eind) groups, have been obtained as yellow-orange to red crystalline solids by the reaction of 1,2-dibromodigermene, (Eind)BrGeGeBr(Eind) (1), with ArLi. In the crystals of 2–5, the digermene cores show a flexible nature adopting a trans-bent geometry with the trans-bent angles (θ) between the Ge–Ge vector and the CEind–Ge–CAr plane of 34.04(12)° (2), 38.3(3)° and 38.8(3)° (3), 33.69(12)° (4) and 39.30(13)° (5). In the UV-vis spectra, strong π–π* absorptions have been observed with an absorption maximum at 451 nm (ε = 1.3 × 104) (2), 455 nm (ε = 9.7 × 103) (3), 480 nm (ε = 1.3 × 104) (4) and 497 nm (ε = 1.4 × 104) (5), retaining the GeGe double bond in solution. The absorption data and DFT calculations provide evidence for the intrinsic π-conjugation between the GeGe chromophore and aromatic rings involving the narrowing of the HOMO–LUMO gaps (ΔE) with the extension of the carbon π-electron systems.