STUDY OF SPECIFIC C-H...N INTRAMOLECULAR INTERACTIONS IN HETEROARYL VINYL ETHERS, ON THE BASIS OF FACTOR-ANALYSIS OF H-1 AND C-13 NMR SPECTRAL PARAMETERS

On the basis of a factor analysis of the H-1 and C-13 NMR spectral parameters of the vinyloxy group in a broad series of aryl and heteroaryl vinyl ethers, it has been established that these parameters change mainly under the influence of the electronic effect of the aromatic fragment and specific C-H...N intramolecular interaction of the alpha-hydrogen atoms of the vinyl group with an endocyclic nitrogen atom. It has been shown that the parameters most sensitive to the specific C-H...N. interaction are the chemical shifts of the alpha-proton and alpha-carbon of the vinyl group, and also the spin-spin coupling constant between these atoms.