Zimmerman

R. Englman and A. Yahalom, in TheJahn Teller Ejfect A Permanent Presence in the Frontiers of Science, M. D. Kaplan and G. Zimmerman, eds.. Proceedings of the NATO Advanced Research Workshop. Boston. Sept. 2000, Kluwer, Dordrecht, 2001. 

Electi ocyclic reactions are examples of cases where ic-electiDn bonds transform to sigma ones [32,49,55]. A prototype is the cyclization of butadiene to cyclobutene (Fig. 8, lower panel). In this four electron system, phase inversion occurs if no new nodes are fomred along the reaction coordinate. Therefore, when the ring closure is disrotatory, the system is Hiickel type, and the reaction a phase-inverting one. If, however, the motion is conrotatory, a new node is formed along the reaction coordinate just as in the HCl + H system. The reaction is now Mdbius type, and phase preserving. This result, which is in line with the Woodward-Hoffmann rules and with Zimmerman s Mdbius-Huckel model [20], was obtained without consideration of nuclear symmetry. This conclusion was previously reached by Goddard [22,39]. 

Strynadka et al., 1996] Strynadka, N., Eisenstein, M., Katchalski-Katzir, E., Shoichet, B., Kuntz, I., Abagyan, R., Totrov, M., Janin, J., Cherflls, J., Zimmerman, F., Olson, A., Duncan, B., Rao, M., Jackson, R., Sternberg, M., and James, M. Molecular docking programs successfully predict the binding of a /3-lactamase inhibitory protein to TEM-1 /3-lactamase. Nature Struct. Biol. 3 (1996) 233-239... 

Zimmerman-Traxler Transition State Ivanov condensation JACS 1957, 7.9, 1920. 

The Zimmerman-Traxler like transition state model can involve either a chair or boat geometry. 

Cyclooctatetraene can be obtained on an industrial scale by metal carbonyl catalyzed thermal tetramerization of acetylene. If cyclooctatetraene is UV-irradiated at low temperature in the presence of acetone, it is reversibly rearranged to form semibullvalene (H.E. Zimmerman, 1968, 1970). 

Barrelene was obtained via a double Diels-Alder reaction from a-pyrone with methyl acrylate (H.E. Zimmerman, I969A). The primarily forming bicyclic lactone decarboxylates in the heat, and the resulting cyclohexadiene rapidly undergoes another Diels-Alder cyclization. Standard reactions have then been used to eliminate the methoxycarbonyl groups and to introduce C—C double bonds. Irradiation of barrelene produces semibullvalene and cyclooctatetraene (H.E. Zimmerman. 1969B). 

B. D. Nahloosky and G. A. Zimmerman, Thermoplastic Elastomers for S olid Propellant Binders, AERPL-TR-86-069, Aerojet Tactical Systems Co., Sacramento, Calif., Dec. 1986. 

D. B. Jacobs and J. Zimmerman, in C. E. Schildknecht and I. Skeist, eds.. Polymerisation Processes, High Polymers, Vol. XXIX. Wiley-Interscience, New York, 1977, pp. 424, 467. A very detailed review of nylon-6,6 polymerization. 

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