Variable electronic effect of silyl groups attached to oxygen

1978 ◽  
Vol 43 (3) ◽  
pp. 746-752 ◽  
Author(s):  
Josef Pola ◽  
Václav Chvalovský
1966 ◽  
Vol 39 (2) ◽  
pp. 412-412 ◽  
Author(s):  
Yoichiro Nagai ◽  
Noboru Machida ◽  
Toshihiko Migita

1980 ◽  
Vol 45 (3) ◽  
pp. 861-875 ◽  
Author(s):  
Josef Pola ◽  
Václav Chvalovský

The electronic effect parameter σ for XYZSi-R compounds as silyl hydrides XYZSiH, alkoxysilanes XYZSiOL (L = alkyl or substituted alkyl) and α-carbofunctional silanes XYZSiCH2Y (Y = Cl and OL) having X, Y and Z substituents of various electron-donating and electronaccepting ability has been established by a linear regression analysis of the IR and NQR data on these compounds. It is shown that no universal scale of the σ constant for silyl XYZSi-groups can be established. The electronic effect transmission of the X, Y and Z substituents through the silicon depends on the type of the intramolecular interaction between the silicon and the R group and the electronic effect parameter of silyl groups should be treated as a variable whose exact value depends on the nature of the particular molecule.


1979 ◽  
Vol 44 (3) ◽  
pp. 750-755 ◽  
Author(s):  
Josef Pola ◽  
Marie Jakoubková ◽  
Václav Chvalovský

Relative basicity of the oxygen in alkoxysilanes (RO)nSi(CH3)3-n having n = 1-4 and various electrondonating and electronwithdrawing groups R measured as Δν(OH) of phenol due to its interaction with these compounds in CCl4 is shown to be chiefly controlled by the electronic effect of substituents R. Linear regression analysis of the Δν(OH) vs n relatioship for individual series (RO)nSi(CH3)4-n suggests the operation of the polarizability effect of RO groups becoming more important with increasing electronwithdrawing nature of R.


Author(s):  
Yi Guan ◽  
Nan Li ◽  
Jiao He ◽  
Yongliang Li ◽  
Lei Zhang ◽  
...  

Herein, we report a post-assembly strategy by growing the bimetallic Co/Zn zeolitic imidazolate frameworks (BIMZIF) on the surface of the customized Mo metal-organic frameworks (MOFs) (Mo-MOF) to prepare the core-shell...


Author(s):  
Shengya Zhang ◽  
Zhuangfei Zhang ◽  
Wencai Yi ◽  
Xin Chen ◽  
Xiaobing Liu

Symmetry ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 502
Author(s):  
Agata J. Pacuła-Miszewska ◽  
Anna Laskowska ◽  
Anna Kmieciak ◽  
Mariola Zielińska-Błajet ◽  
Marek P. Krzemiński ◽  
...  

A series of new bidentate N,S-ligands—aziridines containing a para-substituted phenyl sulfide group—was synthesized and evaluated in the Pd-catalyzed Tsuji–Trost reaction and addition of diethylzinc and phenylethynylzinc to benzaldehyde. A high enantiomeric ratio for the addition reactions (up to 94.2:5.8) was obtained using the aziridine ligand bearing a p-nitro phenyl sulfide group. Collected results reveal a specific electronic effect that, by the presence of particular electron-donating or electron-withdrawing groups in the PhS- moiety, influences the σ-donor–metal binding and the enantioselectivity of the catalyzed reactions.


1978 ◽  
Vol 43 (12) ◽  
pp. 3385-3390 ◽  
Author(s):  
Josef Pola ◽  
Václav Chvalovský
Keyword(s):  

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