The infrared 1H nuclear magnetic resonance, and ultraviolet spectra of some nuclear substituted styryl ketones

Abstract

The synthesis and spectra of several substituted 1-phenylhept-1-en-3-ones are described. The olefinic double bond was shown from infrared and 1H n.m.r. spectroscopy to have the trans-configuration. Correlations have been found of the Hammett and Taft values of the substituents with both the infrared carbonyl frequencies and the τ-values of the olefinic protons. Ultraviolet spectroscopy suggests the loss of planarity of the conjugated system when some ortho-substituents are present.