Studies of Tertiary Amine Oxides. Part115. Carbon - 13 nuclear magnetic resonance spectra of some N-(4-substituted phenyl) piperidine, the corresponding N-oxides, and their thermal-rearrangement product

Abstract

Abstract The carbon-13 chemical shifts of seven N-(4-substituted phenyl) piperidine; the corresponding N-oxides, and their thermal rearrangement products were analyzed and assigned. The N-oxidation effect on the carbon-13 chemical shift is discussed, a correlation of N-oxidation effect with substituent constant (σp, σm, σI and σR) has been studied; dual substituent-parameter equation produce better correlation.