Structure-spectra relationships of aliphatic methyl ethers and primary amines

Abstract

For a series of methyl ethers, CH₃OR, the following properties have been measured: (a) the relative nmr chemical shifts, neat and in carbon tetrachloride solution, of the methyl protons, (b) the relative chemical shifts of the chloroform proton of chloroform in carbon tetrachloride containing methyl ethers, and (c) the infrared shifts and integrated band intensities of the asymmetrical O-CH₃ stretching mode in carbon tetrachloride solution. Both the relative nmr chemical shifts of the methyl ethers and the relative nmr chemical shifts of chloroform in carbon tetrachloride containing methyl ethers are controlled largely by polar and large atom six-number effects of the R group. In carbon tetrachloride solution, the infrared shifts of the asymmetrical O-CH₃ stretching mode for methyl ethers are controlled only partially by polar and large atom six-number effects of the R group. The integrated band intensities of the asymmetrical O-CH₃ stretching mode are controlled largely by polar and large atom six-number effects of the R group.