The stability of the lactone rings of alkyl substituted coumaran-2,3-diones against hydrolysis and alcoholysis is greatly affected by the positions of alkyl substituents. From UV spectral studies it was suggested that methyl substitutions at positions adjacent to the lactone ring contribute to stability for steric reasons.
烷基取代的
香豆素-2,3-二酮的内酯环对
水解和醇解的稳定性在很大程度上受到烷基取代基位置的影响。紫外光谱研究表明,由于立体原因,内酯环邻近位置的甲基取代有助于提高稳定性。