Carbon-13 chemical shifts in some substituted furans and thiophens

Abstract

The ¹³C N.M.R. spectra of a number of substituted furans and thiophens have been determined and individual resonances assigned. The substituent effects which are comparable to those for substitutedbenzene or pyrrole derivatives are discussed. In 2,5-disubstituted compounds, some correlation of the observed resonances and values calculated from the additivity parameters is evident.