Quantitative analysis of steric effects

Gallo, R. J., Roussel, C., Berg, U., The Quantitative Analysis of Steric Effects in Heteroaromatics, 43, 173. 

Heteroaromatic sulfoxides and sulfones ligand exchange and coupling in sulfuranes and //Avo-substitutions, 49, 1 Heteroaromatic systems, Claisen rearrangements in, 42, 203 Heteroaromatics, quantitative analysis of steric effects in, 43, 173 Heterocycles aromaticity of, 17, 255 chiral induction using, 45, 1 containing the sulfamide moiety,... 

The reason for writing this article is that important progress in the quantitative analysis of steric effects in heteroaromatics has been made recently by linear free energy relationships (LFER), geometrical, and theoretical methods. Also, heterocycles have been used to propose and exemplify new concepts and new parameters in physical organic chemistry. 

In Section II, devoted to intermolecular processes, it appeared that most of the quantitative analysis of steric effects was made using a single parameter approach. However, analysis has shown that a correct description of the size of a substituent rests on its preferred conformational states, which are related to the interactions with both the planar heteroaromatic ring to which it is bonded and neighboring groups. This was the topic of Section III. 

Quantitative analysis of steric effects in heteroaromatics, 43, 173 Quaternization... 

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