Identifying Diversity in Nanoscale Electrical Break Junctions
摘要:
The realization of molecular-scale electronic devices will require the development of novel strategies for controlling electrical properties of metallmoleculelmetal junctions, down to the single molecule level Here, we show that it is possible to exert chemical control over the formation of metallmolecule. moleculelmetal junctions in which the molecules interact by pi-stacking The tip of an STM is used to form one contact, and the substrate the other, the molecules are conjugated oligophenyleneethynylenes (OPEs) Supramolecular pi-pi interactions allow current to flow through the junction, but not if bulky tert-butyl substituents on the phenyl rings prevent such interactions For the first time, we find evidence that pi-stacked junctions can form even for OPEs with two thiol contacts. Furthermore, we find evidence for metallmoleculelmetal junctions involving oligophenyleneethynylene monothiols, in which the second contact must be formed by the interaction of the pi-electrons of the terminal phenyl ring with the metal surface
Nanoscale Aryleneethynylene Molecular Wires with Reversible Fluorenone Electrochemistry for Self-Assembly onto Metal Surfaces
摘要:
Two rigid-rod conjugated molecules (11 and 12) of ca. 4 and 7 nm length, respectively, bearing protected terminal thiol groups have been synthesized via multistep Sonogashira coupling reactions and shown to possess reversible cathodic solution electrochemistry arising from reduction of the fluorenone units.
Synthesis and Properties of Functionalized Oligo(arylene) Molecular Wires with Thiolated Termini: Competing Thiol-Au and Nitro-Au Assembly
作者:Xianshun Zeng、Changsheng Wang、Andrei S. Batsanov、Martin R. Bryce、Joanna Gigon、Barbara Urasinska-Wojcik、Geoffrey J. Ashwell
DOI:10.1021/jo902205p
日期:2010.1.1
We report the synthesis by Suzuki cross-coupling methodology of oligo(arylene) molecular wires with protected thiolates at both termini and a central electron-acceptor unit (3,5-dinitrofluorenone, compounds 10−12) or an electron-donor unit [9-(1,3-dithiol-2-ylidene)fluorene, compounds 14−17] in the backbone. Core reagents are 2,7-dibromo-3,5-dinitrofluorenone 7 (obtained by nitration of 2,7-dibromofluorenone)
我们报告的合成通过Suzuki交叉偶联寡(亚芳基)与在两个末端和中心电子受体单元保护硫醇盐分子导线的方法(3,5- dinitrofluorenone,化合物10 - 12)或电子给体单元[9 - (1,3-二硫杂环戊二烯-2-亚基)芴,化合物14 - 17 ]中的骨干。核心试剂是2,7-二溴-3,5-二硝基芴酮7(通过2,7-二溴芴酮的硝化作用获得)和2,7-二溴-9-(4,5-二甲基-1,3-二硫醇-2-亚芳基芴13。已经研究了这些低聚(亚芳基)衍生物的溶液电化学氧化还原性能。含二硝基芴酮的分子的还原CVs显示出三个可逆/准可逆的对,依次产生自由基阴离子,二价阴离子和自由基三阴离子物种,例如对于11 E 1red -1.02 V(vs。THF中的Ag / Ag +)。1,3-二硫杂环戊二烯-2-亚基单元赋予良好的电子供体特性的分子14,15,和16与自由基阳离子形成在观察ë牛约 0.65
A convenient synthesis of ferrocene-(ethynylphenyl)thioacetates
作者:Troy L. R. Bennett、Nicholas J. Long
DOI:10.1039/d3dt02954a
日期:——
A protecting-group strategy can be used to synthesise symmetrical, asymmetrical and multi-ferrocenyl molecular wires, terminated with thioacetates – rare molecules with significant potential in the fabrication of molecular nanoelectronics.