Transmission of substituent effects through extended systems-III. p-Substituted ethyl trans cinnamates and phenylpropiolates

Article abstract of DOI:10.1016/0584-8539(82)80085-8

Infrared data and 13C chemical shifts are reported for a series of ethyl p-substituted trans-cinnamates and ethyl phenylpropiolates.The i.r. values include intensities for the benzene, ethylene and carbonyl vibrations which allow an estimation of resonance effects.The relative importance of the various mechanisms of transmission of substituent effects are discussed and compared to those previously reported for p-substituted trans cinnamonitriles.It is shown that the carbon-carbon triple bond is less efficient in transmitting substituent effects than carbon-carbon double bonds.