Reactive Intermediates and Reaction Mechanisms

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The basic kinetics of reactions which involve the formation and subsequent reactivity of unstable chemical species such as multiradicals and zwitterions will be probed. The concurrent use of ESR, NMR, and optical transient spectroscopy will provide basic mechanistic information which will aid in designing chemical reactions involving highly reactive intermediates from a rational viewpoint. The research topics to be investigated include: (1) the trapping of oxyallyls via dimethylfulvene and related agents; (2) production of disjointed biradicals; (3) confirmation of the spin multiplicity and reactivity of tetramethylene benzene; (4) adjustment of the multiplet gap of biradicals based upon disjointed tetramethyleneethanes; (5) synthesis of polyradicals based upon coupling of two dimethyleneheterocycles via a benzene ring; and (6) synthesis and characterization of stable biradicals. These chemical systems will serve as models for materials with optical, conducting, and magnetic properties of practical importance. %%% This grant from the Organic Dynamics Program supports the continuing work of Professor Jerome A. Berson at Yale University. Professor Berson and his research group will probe very reactive species, called diradicals, which are formed in the intermediate stages of chemical processes and often live for only a few billionths of a second. Information about these intermediates may make it possible design totally new molecules with important chemical and technical properties. The concepts to be derived from this work are critical to the understanding of how molecules conduct electricity and interact with light, and will also aid in the design of chemical systems which can be used to make optical fibers to transmit information in the form of light pulses faster and more efficiently over long distances.