Oxygen-17 nuclear magnetic resonance study of some five-membered heterocyclic derivatives
摘要:
Abstract17O NMR spectra have been obtained in the FT mode for some furan and isoxazole derivatives. The chemical shifts, mainly governed by the electronegativities of the atoms bonded to the central oxygen, are also affected by alkylation on the different positions of the ring systems, which gives rise to β and γ effects similar to those observed for simple aliphatic ethers.