Synthetic, Structural and Mechanistic Metallacyclobutene Chemistry

在这个由无机化学、生物无机化学和金属有机化学计划支持的项目中，加州大学圣地亚哥分校的约瑟夫·奥康纳博士将对金属环丁烯络合物的合成、结构阐明以及形成和反应的机理方面进行研究。奥康纳博士已经发现了一种方法，可以产生一系列晚期过渡金属的金属环丁烯，而这种方法的例子很少，对反应性的研究更少。要研究的反应包括通过与炔烃和烯烃的反应，将金属环丁烯转化为环戊二烯和其他五元环，这些环是有机合成的有用中间体。用时间分辨光谱方法研究了一个钴环丁烯配合物中磷供体的取代反应中观察到的一种新的光致变色效应。该项目涉及一类新的有机金属化合物的合成和反应性的基础研究，该化合物被称为金属环丁烯。这些研究感兴趣的例子包括后期过渡元素。主要目标是开发新的合成方法，可用于天然产物及其同系物的全合成。其中一些最终可能会被应用于新的药物。

In this project which is supported by the Inorganic, Bioinorganic and Organometallic Chemistry Program, Dr. Joseph O'Connor of the University of California, San Diego will pursue an investigation of the synthesis, structural elucidation, and mechanistic aspects of formation and reaction of metallacyclobutene complexes. Dr. O'Connor has already discovered one method that should produce a range of metallacyclobutenes of late transition metals where there is a paucity of examples and even fewer studies of reactivity. Reactions to be studied include conversion of the metallacyclobutenes to cyclopentadienes and other five-membered rings, which are useful intermediates for organic synthesis, by reactions with alkynes and olefins. A novel photochromic effect that was observed in the substitution reaction of phosphorus donors in one cobaltacyclobutene complex will be examined by time-resolved spectroscopic methods. This project involves fundamental investigations of the synthesis and reactivity of a new class of organometallic compound known as metallacyclobutenes. The examples of interest for these studies contain late transition elements. The major objective is the development of new synthetic methods that may be used in total synthesis of natural products and their homologs. Some of these may ultimately find application as new pharmaceuticals.