Stereopopulation control

Milstein S, Cohen LA (1972) Stereopopulation control. I. Rate enhancement in the lactoni-zations of o-hydroxyhydrocinnamic acids. J Am Chem Soc 94 9158-9165... 

Milstien, S., Cohen, S. A. Rate acceleration by stereopopulation control Models for enzyme action. Proc. Natl. Acad. Sci. U.S. 67, 1143—1147 (1970). 

Stereopopulation Control on Cyclometallation Reactions and the Stability of Very Large Chelate Rings... 

The Thorpe-Ingold or gem-Dialky l Effect—Stereopopulation Control or Orbital Steering... 

Stepwise reaction, 230 Stereopopulation control, 367 Sterie compression, 367 Steric constant. 335, 342 Sterie effect aliphatic, 340, 342 aromatic, 335... 

Approximation and orientation This is the entropic contribution (Page, 1977). Enzymatic reactions take place in the confines of the enzyme-substrate complex. The catalytic groups are part of the same complex as the substrate. This proximity/propinquity and appropriate positioning of substrate molecules with respect to the catalytic groups in the active site via stereopopulation control or orbital steering may contribute to a rate enhaucement with a factor of 10 to 10. ... 

Since the intramolecular reactivity often achieves the highest limits of the enzyme reaction rates and even rivals them [9,10], a special attention has been paid to studying its sources. A variety of useful rules and concepts, such as entropy and stereopopulation control, orbital steering, propinquity, and spatiotemporal hypotheses, have been evolved and their scope and limitations critically reviewed [11-13]. While differing from one another in their terms and emphases, they are common in reflecting in their essence a general principle of steric fitness of initial and transition state structures of fast intramolecular reactions. 

Stereopopulation control Substrate anchoring Vibrational activation Vibrational activation entropy Orbital perturbation theory Group transfer hydration Electrostatic stabilization Electric field effect... 

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