Discovery-based dye chemistry: synthesis and properties of new functional molecules, ligands, and coordination complexes

有机染料和颜料已被用于我们的世界（纺织品，油漆，涂料等）数千年，最初使用天然染料，但现在主要使用合成染料。有色分子还可以具有其他能力，如氧化还原活性、发射、光化学活性或与金属结合的能力。这些特性使它们在催化、太阳能转换、健康和医学等广泛的应用中非常有用。许多研究小组的焦点是针对特定应用优化特定已知类型的染料。该优化过程涉及染料/络合物的几种相关衍生物的合成（通常通过改变取代基）和开发结构-性质关系。我的团队的方法本质上更基本。我们的目标是设计，制造，研究和开发新型染料及其金属络合物。我们希望使新的分子具有有趣/创新/有用的特性（例如物理学，氧化还原）。我们的长期目标是为上述应用领域的其他研究人员拓宽分子工具包。我们特别感兴趣的分子是在可见光谱和近红外线的低端强烈的光吸收剂。这个光谱区域对于几个研究领域来说是至关重要的，但是在这里使新的发色团吸收光是具有挑战性的。 该提案的一部分集中在我们最近成功地将著名的纺织颜料靛蓝转化为更可溶的二亚胺类似物。本提案目前/未来的目标领域将包括：（1）通过合成和表征新的Nindigo配体衍生物以及新的金属，进一步探索Nindigo络合物的氧化还原/光学性质;（2）Nindigo络合物作为电子和质子库的反应性研究;（3）以新的Nindigo结构类型为目标的合成探索性工作，以期发现制备近红外吸收分子和复合物的新方法。 该提案的第二个重点是确定新型染料配体结构，这些结构将与金属结合并具有极不寻常的光学性质，即吸收非常高能量（近红外）的光。 本申请提出了几种三齿的pi扩展变体，其由杂环结构单元如吡咯、吲哚和咔唑构成;所提出的配体pi系统被设计为导致异常低的能量（近红外）吸收（作为游离分子和与金属结合），同时使用取代基来保持稳定性。这一领域的分项目将涉及有机/杂环合成，以及合成配位化学沿着上述表征方法。

Organic dyes and pigments have been used to colour our world (textiles, paints, coatings, etc) for millennia, originally using naturally occurring dyes but now mostly using dyes made synthetically. Coloured molecules can also possess other capabilities such as redox activity, emission, photochemical activity, or the ability to bind to metals. These properties make them useful in a huge range of applications including catalysis solar energy conversion, and health & medicine. A focus of many research groups is to optimize a particular known type of dye for a particular application. This optimization process involves the synthesis of several related derivatives of the dye/complex (typically by changing substituents) and developing structure-property relationships. My group's approach is more fundamental in nature. We aim to design, make, study, and develop new kinds of dyes and metal complexes thereof. We want to make new molecules have properties (e.g. photophysical, redox) that are interesting/innovative/useful. Our long term goals are to broaden the molecular toolkit for other researchers in the application-oriented areas mentioned above. We are particularly interested in molecules that are intense light absorbers at the low end of the visible spectrum and the near-infrared. This spectral region is critical for several fields of research but it is challenging to make new chromophores absorb light here. Part of this proposal focuses on our recent success in converting the famous textile pigment indigo into more soluble diimine analogues. Current/future target areas in this proposal will include (1) further exploration of the redox/optical properties of Nindigo complexes, through the synthesis and characterization of new Nindigo ligand derivatives as well as new metals; (2) reactivity studies of Nindigo complexes as electron and proton reservoirs; and (3) synthetic exploratory work targeting new Nindigo structure types, with a view to uncovering new ways to make near-infrared absorbing molecules and complexes. A second thrust of this proposal identifies new types of dye ligand structures that will bind to metals and possess extremely unusual optical properties, namely absorption of very energy (near infrared) light.  This application proposes several tridentate, pi expanded variants that are constructed from heterocyclic building blocks such as pyrroles, indoles, and carbazoles; the proposed ligand pi systems are designed to lead to exceptionally low energy (near IR) absorption (both as free molecules and bound to metals) while using substituents to maintain stability. The sub-projects in this area will involve organic/heterocyclic synthesis, as well as synthetic coordination chemistry along with the characterization methods listed above.