Jay K. Kochi
Robert A. Welch Professor
	Office: 212 Fleming Phone: (713) 743-3293 Email: jkochi@uh.edu Education B. S., University of California, 1949 Ph.D., Iowa State University, 1952 Honors, Fellowships, etc. James Flack Norris Award, 1981 U.S. National Academy of Sciences, 1982 Professeur Associe, University of Rennes, France, 1983 Faulk-Plaut Lecturer, Columbia University, New York, 1984 (more...)

Research Interests

Physical Organic and Organo-metallic Chemistry      The broad varieties of organic and organometallic reactions merge into a common unifying mechanism by considering all nucleophiles and electrophiles as electron donors (D) and electron acceptors (A), respectively. Comparison of outer-sphere and inner-sphere electron transfers provides the thermochemical basis for the generalized free energy relationship for electron transfer (FERET) that has wide predictive applicability to organic and organometallic reactions such as electrophilic aromatic substitutions, olefin additions, organometallic cleavages, etc. The FERET is based on the conversion of the weak nucleophile-electrophile interactions extant in the ubiquitous electron donor-acceptor precursor complex [D:A] to the radical ion pair [D+, A-], for which the free energy change can be evaluated from the charge-transfer absorption spectra. FERET analysis thus indicates that the charge-transfer ion-pairs [D+, A-] are energetically equivalent to the transition states for nucleophile/electrophile transformations. The behavior of such ion pairs can be directly observed immediately following the irradiation of the charge-transfer bands of various EDA complexes with a 25-ps laser pulse. Such studies confirm the radical ion pair [Arene+, NO2] as a viable intermediate in electrophilic aromatic nitration, as presented in the electron-transfer mechanism between arenes and the nitryl (NO2+) electrophile.      The ability of organometallic species to undergo ready oxidation also constitutes an important facet to their utility as ultimate reagents in organic synthesis and as reactive intermediates in catalytic organic reactions. Thus, the prototypical Grignard addition to carbonyl groups and Grignard coupling with akyl halides represent, in their most fundamental constructs, the oxidation of the nucleophilic organomagnesium reagent. The different electron donors (D) and acceptors (A) are: Electron donor (D) Anions Reductant Nucleophile Base (Brønsted, Lewis, HSAB) (Electron rich) Electron acceptor (A) Cations Oxidant Electrophile Acid (Electron poor) the above constitute reactant pairs that are traditionally considered with more specific connotations in mind, such as nucleophiles and electrophiles in bond formation, reductant and oxidant in electron transfer, bases and acids in adduct production, and anion and cations in ion-pair annihilation. In the latter case, the preequilibrium formation of contact ion pairs has its counterparts that are variously described as an encounter complex, a non-bonded electron donor-acceptor complex, a precursor complex, or a contact charge-transfer complex. In order to illustrate the utility of the electron donor-acceptor concept as a unifying theme in the delineation of the organometallic reactions of anions and cations, representative examples are being examined.