Star Porphyrazines, Solitaire Phthalocyanines and Related Multimetallic Macrocycles

西北大学化学系的Brian M. Hoffman博士与英国伦敦帝国理工学院化学系的Anthony G. M. Barrett博士进行了一项合作项目，该项目得到了化学学部无机、生物无机和有机金属化学项目的支持，旨在合成和研究星型卟啉类、酞菁类和相关的多金属大环。将合成一系列外围被杂原子取代的卟啉类化合物。这些将转化为配合物，金属结合到外围杂原子和中心大环的核心。将几个金属卟啉单元通过外围金属桥连接起来形成扩展阵列。由于电子离域和通过大环pi系统的金属-金属相互作用，所得到的配合物将具有不同寻常的光谱、磁性或电学性质。含有多种金属的化合物通常具有独特的磁性和电子特性。在这个项目中，将准备一系列这样的材料。这种特殊的设计涉及一个中心金属，它被其他原子（大环配体）的刚性结构所包围，附加的金属附着在上面。这就形成了星形或线性的金属原子阵列。这些有望有多种应用，包括生物医学光学成像、光学传感器、手性物质分离和催化。该项目涉及英国的一个小组和西北大学的一个小组之间的合作，前者将制备大环配体，后者将负责将配体转化为金属配合物。学生将在小组之间进行交换，因此将接受合成有机和金属化学方面的极其广泛的培训。这项合作也为美国学生提供了体验现代科学的国际层面的机会。

Dr. Brian M. Hoffman, Chemistry Department, Northwestern University, is supported by the Inorganic, Bioinorganic, and Organometallic Chemistry Program of the Chemistry Division for a collaborative project with Dr. Anthony G. M. Barrett, Chemistry Department, Imperial College of Science and Technology, London, England, aimed at synthesis and study of star porphyrazines, solitaire phthalocyanines and related multimetallic macrocycles. A series of porphyrazines that are peripherally substituted with heteroatoms will be synthesized. These will be converted into complexes with metals bound to the peripheral heteroatoms and to the core of the central macrocycle. Extended arrays will be formed by connecting several of the metalla-porphyrazine units through peripheral metal bridges. The resultant complexes will have unusual spectroscopic, magnetic, or electrical properties properties due to electron delocalization and metal-metal interactions through the macrocyclic pi-system. Compounds which contain several metals often have unique magnetic and electronic properties. In this project a series of such materials will be prepared. The specific design involves a central metal which is surrounded by a rigid structure of other atoms (a macrocyclic ligand) to which additional metals are attached. This results in star-shaped or linear arrays of metal atoms. These are expected to have a diversity of applications including biomedical optical imaging, optical sensors, the separation of chiral substances, and catalysis. The project involves the collaboration between a group in England, where the macrocylic ligands will be prepared, and one at Northwestern University, which will be responsible for the conversion of the ligands into metal complexes. Students will be exchanged between the groups and thus will receive an extremely broad training in synthetic organic and metal chemistries. The collaboration also provides the opportunity for US students to experience the international aspects of modern science.