A library of symmetrical linear oligothiophene was prepared employing decarboxylative cross-coupling reaction as the key transformation. Thiophene potassium carboxylate salts were used as cross-coupling partners without the need of co-catalyst, base, or additives. This method demonstrates complete chemoselectivity and is a comprehensive greener approach compared to the existing methods. The modularity
Preparation and Characterization of π-Stacking Quinodimethane Oligothiophenes. Predicting Semiconductor Behavior and Bandwidths from Crystal Structures and Molecular Orbital Calculations
作者:Daron E. Janzen、Michael W. Burand、Paul C. Ewbank、Ted M. Pappenfus、Hiroyuki Higuchi、Demetrio A. da Silva Filho、Victor G. Young、Jean-Luc Brédas、Kent R. Mann
DOI:10.1021/ja0484597
日期:2004.11.1
is dominated by an intense (e ≅ 100 000 M-1 cm-1) low energy π−π* transition that has a λmax ranging between 648 and 790 nm. All X-ray crystalstructures exhibit very planar quinoidal backbones and short intermolecular π-stacking distances (3.335−3.492 A). Structures exhibit a single π-stacking distance with parallel cofacial stacking (sulfur atoms of equivalent rings pointed in the same direction)
已经研究了一系列新的醌二甲烷取代的三联噻吩和四联噻吩低聚物,以与先前研究的醌型低聚噻吩进行比较,后者在薄膜晶体管器件中表现出高迁移率和双极传输行为。每个新的醌型噻吩衍生物在 0.85 到 1.32 V 之间显示出可逆的单电子氧化,在 1.37 到 1.96 V 之间显示出准可逆的单电子第二氧化,以及 -0.05 到 -0.23 V 之间的可逆双电子还原。每种化合物的 UV-vis-NIR 光谱主要由强 (e ≅ 100 000 M-1 cm-1) 低能量 π-π* 跃迁主导,其 λmax 范围在 648 和 790 nm 之间。所有 X 射线晶体结构都表现出非常平面的醌型主链和较短的分子间 π 堆积距离 (3.335−3.492 A)。