Functionalized Thiophene-Based [7]Helicene: Chirooptical Properties versus Electron Delocalization

被引：53

作者：

Rajca, Andrzej ^{[1
]}

Pink, Maren ^{[2
]}

Xiao, Shuzhang ^{[1
]}

Miyasaka, Makoto ^{[1
]}

Rajca, Suchada ^{[1
]}

Das, Kausik ^{[1
]}

Plessel, Kristin ^{[1
]}

机构：

[1] Univ Nebraska, Dept Chem, Lincoln, NE 68588 USA

[2] Indiana Univ, Dept Chem, IUMSC, Bloomington, IN 47405 USA

来源：

JOURNAL OF ORGANIC CHEMISTRY | 2009年 / 74卷 / 19期

基金：

美国国家科学基金会;

关键词：

CROSS-CONJUGATED OLIGOTHIOPHENES; ASYMMETRIC-SYNTHESIS; OPTICAL-PROPERTIES; CHIROPTICAL PROPERTIES; BAND-GAP; HELICENES; ABSORPTION; RESOLUTION; SYSTEMS; ROUTE;

D O I：

10.1021/jo901769c

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

The functionalized, enantiomerically pure [7]helicene 1 derived from bis(benzodithiophene) functionalized with four heptyl groups is prepared from 1,8-dibromo-4,5-diheptylbenzo[1,2-b:4,3-b']dithiophene building block 2. Such [7]helicene structure, functionalized with bromines at the terminal positions of the helicene inner rim and multiple solubilizing alkyl groups, is an attractive building block for long [n]helicenes and oligo[7]helicenes. Chirooptical properties and the degree of electron delocalization are determined and compared to those of analogous carbon-sulfur [7]helicene and [7]helicenes derived from benzodithiophene to provide a correlation between chirooptical properties and the degree of electron delocalization. [7]Helicene 1 possesses a moderately increased electron delocalization, but its chirooptical properties are similar to those for analogous [7]helicenes with relatively lower electron delocalization, indicating that chirooptical properties are not significantly affected by electron delocalization for this series of [7]helicenes. Molecular structures of racemic [7]helicene 1 and its benzodithiophene building block 2 are confirmed by single-crystal X-ray analysis. Crystals of 2 are chiral and adopt the shape of long, flexible, flat needles that can be readily bent.

引用

页码：7504 / 7513

页数：10

共 81 条

[21]

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[22] Probing the chiroptical response of a single molecule [J].