Regularized regression analysis of digitized molecular structures in organic reactions for quantification of steric effects

2017 ◽  
Vol 38 (21) ◽  
pp. 1825-1833 ◽  
Author(s):  
Shigeru Yamaguchi ◽  
Takahiro Nishimura ◽  
Yuta Hibe ◽  
Masaki Nagai ◽  
Hirofumi Sato ◽  
...  
2019 ◽  
Vol 43 (3) ◽  
pp. 1478-1486
Author(s):  
Lei Xu ◽  
Liping Jiang ◽  
Shasha Li ◽  
Guofang Zhang ◽  
Weiqiang Zhang ◽  
...  

Electronic and steric effects of the substituents in 1,3-ynones play key roles in the product distribution and molecular structures.


Polyhedron ◽  
2001 ◽  
Vol 20 (22-23) ◽  
pp. 2829-2840 ◽  
Author(s):  
Joanne M. Holland ◽  
Colin A. Kilner ◽  
Mark Thornton-Pett ◽  
Malcolm A. Halcrow

1961 ◽  
Vol 39 (8) ◽  
pp. 1638-1644 ◽  
Author(s):  
J. Trotter

The structures of m-dinitrobenzene and p-dinitrobenzene have been refined by three-dimensional (Fo—Fc) syntheses. The results indicate that both nitro groups in each molecule are twisted 11° out of the aromatic plane, about the C—N bonds, in contrast to nitrobenzene, where the whole molecule is completely planar. These molecular configurations are shown to be in accord with those which might be expected from intramolecular steric effects. The dimensions of the three molecules have also been compared.


1986 ◽  
Vol 41 (7) ◽  
pp. 895-903 ◽  
Author(s):  
Tadeusz Marek Krygowski ◽  
Günter Häfelinger ◽  
Josef Schüle

AbstractThe angular variations of molecular structures calculated for 17 monosubstituted derivatives of benzene by use of ab initio analytical gradient optimization at the STO -3G level have been correlated by multiple linear regression analysis with Mulliken σ- and π-electron charge densities at corresponding ring carbon atoms. Variations of angles γ at meta positions are solely due to π-electron effects (R = 0.961). Changes in angles β at ortho positions are independent of σ- or π-electron effects but may be related to steric effects (R = 0.719) alone or additionally to charge densities on ortho protons (for dual regression R = 0.846). Angles a at ipso atom s depend significantly on both, σ- and π-electron charge densities in the ratio of 70% to 21% with R = 0.974 for dual regression. Variations of angles δ para-positions depend on all three effects considered (with correlation coefficient for a triple regression R = 0.951) in the ratio 37.6% :2 8 .3% : 34.1% for steric effects, σ- and π-electron charge densities, respectively.


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