Reaction Topology

Silyl Nitronates in Henry Reactions Topologically, condensations of SENAs with carbonyl and nitroso groups, as well as with an imino fragment, belongs to Henry reactions. 

Mezey, P.G., Reaction Topology Manifold Theory of Potential Surfaces and Quantum Chemical Synthesis Design, in Chemical Applications of Topology and Graph Theory, Elsevier Sci. 

The spectroscopic and kinetic data from this reaction indicated the existence of a long sought catalytic reaction topology, bimetallic catalytic binuclear elimination. The kinetic data provided a linear-bilinear form in organometallics [95]. One term represented the classic unicyclic rhodium catalyzed hydroformylation and the other represented the attack of manganese hydride carbonyl on an acyl rhodium tetracarbonyl species. A representation of the interconnected topology is shown in Figure 4.12. 

Figure 4.12 The proposed reaction topology for the simultaneous interconnected unicyclic Rh and bimetallic Rh-Mn CBER hydroformylation reactions. (C. Li, E. Widjaja, M. Garland, J. Am. Chem. Soc., 2003, 725, 5540-5548).

Figure 4.1S Representation of the three primary steps for the generic inverse problem in chemical kinetics including homogeneous catalysis. In situ spectroscopic data is represented by 4kexv Tbe inverse spectroscopic problem (Eq. (2)), which is the focus of this chapter, is represented by S [,s, Ojxv The inverse problem associated with stoichiometries and reaction topology is represented by r rxs moles, reactions, extents of reaction and reaction stoi-...

This neighbor relation is similar to the "symmetric strong neighbor relation" between some potential surface catchment regions of reaction topology, used in the analysis of reaction mechanisms [106,343-345]. 

P.G. Mezey, "Reaction Topology," in Applied Quantum Chemistry, Proceedings of the Hawaii 1985 Nobel Laureate Symposium on Applied Quantum Chemistry, V.H. Smith, Jr., H.F. Schaefer III, and K. Morokuma (Eds.), Reidel, Dordrecht, 1986, pp. 53-74. 

P.G. Mezey, "Reaction Topology and Quantum Chemical Molecular Design on Potential Energy Surfaces", in New Theoretical Concepts for Understanding Organic Reactions, J. Bertran and I.G. Csizmadia (Eds.), Nato ASI Series, Kluwer Academic Publishers, Dordrecht, 1989, pp 55-76. 

The reaction mechanism shown in Figure 6 suggests the involvement of several proton transfer reactions and one would expect the participation of amino acid residue as acid/base catalysts. In a systematic mutagenesis study, the replacement of amino acid residues lining the active site cavity had only minor impact on catalytic rates. This suggests that the contribution of enzyme catalysis is mainly entropic, via the generation of a favorable reaction topology. 

Mock et al. [44] have shown that cucurbituril 48 catalyzes the 1,3-dipolar cycloaddition shown in Scheme 1-13. Here, cucurbituril acts as a linear template note that linear refers to the reaction topology and not to the shape of the template. 49 and 50 bind inside the cavity of 48 by hydrogen bonding between the ammonium groups and the rims of the cucurbituril. The reaction between 49 and 50 is made faster and more regiospecific clean formation of 51 occurs. 

P. G. Mezey, Theor, Chim. Acta, 63, 9 (1983). The Topology of Energy Hypersurfaces, II. Reaction Topology in Euclidian Spaces. 

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