Linearly Conjugated Phosphacarbon Organometallics

在技术小型化的持续推动下，现代化学科学面临的挑战之一是在分子尺度上提供电子元件。这通常是通过采用不饱和的富碳分子来解决的，这些分子现在广泛应用于导电聚合物（所谓的分子线）和普通有机电子产品（如oled，场效应晶体管（ofet）和光伏（opv））的小分子组件。将金属和/或杂原子（如氮）结合到此类分子中提供了增强和控制其光活性和导电性的有效手段，因此是重要的持续研究课题。目前特别关注的是含磷分子（“磷碳”）在这些角色中的应用，这正在被广泛研究。然而，在这种情况下，磷碳化合物的使用尚未渗透到有机金属体系中；这部分是由于缺乏合适的合成方法和一些最简单的有机金属磷碳化合物难以接近。最近，PI开发了第一个将最简单的磷酸碳片段“CP”（cyaphide，氰化物的直接类似物）作为线性共轭链的一部分的化合物，利用有机金属支架。在这些化合物的电子和光解行为中（与经典的碳基系统相比），cyaphide单元的显著参与和影响是显而易见的，使它们特别有趣。该项目将以这些初步进展为基础，开发这类化合物，以实现以金属为中心的氧化还原过程的电化学稳定性和可逆性，并探索它们的导电（和光吸收）特性。进一步的合成路线将被研究和开发，以获得基于改性有机金属支架的更广泛的化合物，增加对电子特征的可用控制。还将探索开发更复杂的磷酸碳衍生物（例如CC-CP部分）的范围。因此，该项目将发展基础合成科学和物理理解，以支持（直接和间接）应用分子电子学不断扩大的领域的未来发展。

One of the challenges for modern chemical science is to furnish electronic components on a molecular scale, driven by the continuing impetus for technological miniaturisation. This is typically addressed by employing unsaturated, carbon-rich molecules, which now feature widely in conducting polymers (so-called molecular wires) and as small molecular components of common organic electronics such as OLEDs, field-effect transistors (OFETs) and photovoltaics (OPVs). The incorporation of metals and/or heteroatoms (e.g. nitrogen) into such molecules offers an effective means of enhancing and controlling their photo-activity and conductivity and is thus the subject of significant on-going research. Particular current interest surrounds the use of phosphorus-containing molecules ('phosphacarbons') in such roles, which is being widely investigated. However, the use of phosphacarbons in this context has not yet permeated the organometallic regime; this is due in part to a lack of suitable synthetic methodology and perceived inaccessibility of some of the simplest organometallic phosphacarbons. Recently, the PI has developed the first compounds to incorporate the simplest phosphacarbon fragment 'CP' (cyaphide, the direct analogue of cyanide) as part of a linearly conjugated chain, exploiting an organometallic scaffold. Significant involvement and influence of the cyaphide unit is manifest in the electronic and photolytic behaviour of these compounds (compared with classical carbon-based systems), rendering them of particular interest. This project will build upon these preliminary advances, developing this class of compounds toward achieving electrochemical stability and reversibility of metal-centred redox processes, and exploring their conductive (and photo-absorptive) properties. Further synthetic routes will be investigated and developed to enable access to a broader range of compounds, based on modified organometallic scaffolds, increasing available control over electronic features. The scope for developing more complex phosphacarbon derivatives (e.g. the CC-CP moiety) will also be explored. This project will, therefore, develop the fundamental synthetic science and physical understanding to underpin (directly and indirectly) future developments in the expanding field of applied molecular electronics.