31P NMR measurement of the homolysis rate constant of the C-ON bond of β-phosphorylated alkoxyamines

Abstract

In the presence of an excess of various alkyl radical scavengers or nitroxide reductants (TEMPO, phenylhydrazine and thiophenol), 31P NMR monitoring was used to determine the homolysis rate constant (kd) of β-phosphorylated alkoxyamines. The kd values for a mixture of diastereoisomeric alkoxyamines can be obtained in a single experiment and the formation of reaction products can be followed. The measured values were in good agreement with those obtained with other approaches involving chromatography or electron paramagnetic resonance (EPR).