Carbon-13 NMR spectra of methylated cyclobutanes and ethyl cyclobutane-carboxylates
摘要:
AbstractThe 13C NMR spectra of cyclobutane and seven methylated homologs and of ethyl cyclobutanecarboxylate and five isomeric diethyl cyclobutanedicarboxylates are reported and substituent parameters for methyl groups in methylcyclobutanes are calculated. Of note is a sizeable and nearly configuration‐independent upfield shifting γ‐effect.