Kawase Takeshi, Nishida Jun-ichi
Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo, 671-2280, Japan.
Chem Rec. 2015 Dec;15(6):1045-59. doi: 10.1002/tcr.201402093. Epub 2015 Apr 20.
Polycyclic conjugated systems bearing carbocyclic five-membered rings have attracted much attention due to their novel electronic properties and utility in organic electronic devices. Despite possessing a 4nπ electron periphery, dibenzopentalenes have a planar structure and are fairly stable. Thus, appropriate modifications should provide desirable electronic properties. Recently, we have discovered novel Ni-catalyzed coupling reactions that constitute a versatile new route to dibenzopentalene derivatives from readily available o-bromoethynylbenzenes. Moreover, we developed another dibenzopentalene synthesis using indenone derivatives as important intermediates. These methods are applicable to π-extended pentalene derivatives possessing various functional groups and aromatic ring systems. Among them, a dinaphthylpentalene derivative shows a high hole mobility (1.8 × 10(-3) cm(2) V(-1) s(-1) ) for an amorphous material. Furthermore, this is the first pentalene derivative that can be employed as a p-type material for organic heterojunction photovoltaic cells (PCE = 0.94%, V(OC) = 0.96 V) and as organic thin-film semiconductors.
带有碳环五元环的多环共轭体系因其新颖的电子性质以及在有机电子器件中的应用而备受关注。尽管二苯并戊搭烯具有4nπ电子外围，但它具有平面结构且相当稳定。因此，适当的修饰应能提供理想的电子性质。最近，我们发现了新型镍催化的偶联反应，该反应构成了一条从易得的邻溴乙炔基苯制备二苯并戊搭烯衍生物的通用新途径。此外，我们开发了另一种以茚酮衍生物为重要中间体的二苯并戊搭烯合成方法。这些方法适用于具有各种官能团和芳香环体系的π-扩展戊搭烯衍生物。其中，一种二萘基戊搭烯衍生物对于非晶材料显示出高的空穴迁移率（1.8×10⁻³ cm² V⁻¹ s⁻¹）。此外，这是第一种可作为有机异质结光伏电池的p型材料（光电转换效率PCE = 0.94%，开路电压V(OC) = 0.96 V）以及有机薄膜半导体的戊搭烯衍生物。
