¹³C NMR spectroscopic studies were performed for carbonyl compounds having a hydroxyl group, a carboalkoxy group, an acetoxy group, or a carboxyl group in various solvents with different polarities for observation of their behaviors of ¹³C NMR chemical shifts of carbonyl carbons in solutions. It was found that the chemical shifts of the carbonyl carbons in ¹³C NMR have good correlation with the empirical parameter for solvent polarities, E_T^N, depending on the structures. Inter- or intramolecular hydrogen bonding and dipolar-dipolar interactions appear to play a key role in this observation.

中文翻译：

---

¹³ C NMR光谱研究各种溶液中羰基化合物的行为

在具有不同极性的各种溶剂中，对具有羟基，碳烷氧基，乙酰氧基或羧基的羰基化合物进行¹³ C NMR光谱研究，以观察其在溶液中的羰基碳的¹³ C NMR化学位移行为。发现在¹³ C NMR中羰基碳的化学位移与溶剂极性的经验参数E _T ^N取决于结构，具有很好的相关性。分子间或分子内氢键和偶极-偶极相互作用似乎在这一观察中起关键作用。