Talk given by Prof. Kenneth N. Raymond Chemistry Department, University of California at Berkeley USA Abstract (sorry, figures are missing): The metal-ligand host shown at right binds cationic guests selectively and strongly in water (Ka up to 105 M-1) [1, 2]. Isotope effects on guest binding and exchange are observed [3]. Applied and solvent internal pressures are shown to increase the barrier to bond rotation in encapsulated guests [4]. This host is shown to catalyze the cyclization of monoterpene derivatives while excluding water from reactive intermediates. This property is also observed in an enyne cyclization by an encapsulated gold catalyst [5]. The Nazarov cyclization to give pentamethylcyclopentadiene is accelerated 2 million times inside the cluster due to enzyme-like stabilization of the transition state, as shown. References: [1] D.L. Caulder, K.N. Raymond, Acc. Chem. Res. 1999, 32, 975. [2] C. Sgarlata, J.S. Mugridge, M.D. Pluth, B.E.F. Tiedemann, V. Zito, G. Arena, K.N. Raymond, J. Am. Chem. Soc. 2010, 132, 1005. [3] J.S. Mugridge, R.G. Bergman, K.N. Raymond, J. Am. Chem. Soc. 2012 134, 2057. [4] J.S. Mugridge, A. Zahl, R. van Eldik, R.G. Bergman, K.N. Raymond, J. Am. Chem. Soc. 2013 135, 4299. [5] W.M. Hart-Cooper, K.N. Clary, F.D. Toste, R.G. Bergman; K.N. Raymond, J. Am. Chem. Soc. 2012 134, 17873. [6] C. J. Hastings, R. G. Bergman and K. N. Raymond, Chem. Eur. J. 2014, 20, 3966 – 3973 .

This event is part of the eventgroup INT Talks

Homepage
https://www.int.kit.edu/events.php

Speaker
Prof. Kenneth N. Raymond

Chemistry Department, University of California at Berkeley
http://www.cchem.berkeley.edu/knrgrp/home.html

Organizer
Prof. Dr. Annie Powell
Institut für Anorganische Chemie und Institut für Nanotechnologie
Karlsruher Institut für Technologie (KIT)
Kaiserstr. 12
76131 Karlsruhe
Mail: annie powell ∂does-not-exist.kit edu
https://www.int.kit.edu/powell.php

Targetgroup
Interested / Everyone