Oxygen-17 nuclear magnetic resonance study of some oxirane derivatives

The ¹⁷O chemical shifts of seventeen variously substituted oxiranes have been measured in CDCI₃ solution. Deviations of δ_o from additivity have been interpreted in terms of steric effects and loss of conjugation. Moreover, in the case of certain cis- and trans-dimethyl-substituted compounds, ¹⁷O NMR allows a differentiation between the different molecular configurations.