Interaction Between Molecule Fragments Unbound by Chemical Bonds Through the Space during NMR ¹H Spectra Registration

The Influence of Substituents Nature on the Chemical Shifts Values of Methyl Protons in the 1H NMR Spectra of 1,1,2,2-Tetrasubstituted Arylpropanes

“…Interaction of unbound fragments "K" and "M" through the space expressed in the deviation of spectral parameters of the fragment "M" from the anticipated values. Such deviation we have previously shown repeatedly for different kinds of compounds including compounds of general formula p-X-C 6 H 4 -CRR 1 CH 2 CH 3 (ІІІ) [1].…”

“…Base spectral parameters (for short, BSP) of terminal methyl groups (fragment "M"), i.e., the chemical shifts of the methyl protons are denoted usually symbol δ СН3 though, as it is written above, we still tend to believe there is little interaction adopted in this paper equal about -20 mlrd. (instead of the proposed earlier [1] values -70 mlrd., if a value of W = 1.00 ppm).…”

“…Therefore, the substituents R 1 and R 2 include alkyls, aralkyls, aryls, hydroxymethyl, carboxyl, carbalkoxyl and other similar functional groups. Other substituents (Y and Z) can be all the various functionalized groups including substituents bonded to the carbon atoms C 1 or C 2 through carbonheteroatom bonds, as well as alkyl groups and hydrogen atoms also.…”

“…Ar -C 1(α) YR 1 -C 2(β) ZR 2 -C 3(γ) H 3 (IV) We have specifically chosen different designations for each of the two substituents: Y and R 1 at C 1 , and also Z and R 2 at C 2 . As mentioned above it is the nature of the substituents, just determines the difference in "families" of compounds of general formula IVNn.…”

“…Previously [1] we choose the optimal, in our opinion, structures of etalon compounds. The spectral data of these structures appear as "desirable" data for comparison with similar spectral parameters of studied arylpropanes derivatives IVNn.…”