外型和内型C-2位单取代降冰片烯衍生物的核磁共振波谱研究

C-2位单取代降冰片烯衍生物中降冰片烯环存在各向异性，且多数为外型和内型异构体的混合物，导致其结构解析困难.针对这一问题，本文在制备了单一构型的C-2位羧基和羟甲基取代的降冰片烯衍生物的基础上，利用¹H NMR、DEPT135、¹H-¹H COSY、¹H-¹³C HMQC、¹H-¹H NOESY谱和相应的耦合裂分信息，对外型-5-降冰片烯-2-羧酸、内型-5-降冰片烯-2-羧酸、外型-5-降冰片烯-2-甲醇和内型-5-降冰片烯-2-甲醇的¹H和¹³C NMR信号进行归属，并探讨了降冰片烯衍生物的取代基种类及空间构型对¹H NMR化学位移的影响.

NMR Spectroscopic Studies on (exo,endo) C-2 Monosubstituted Norbornene Derivatives

The ¹H NMR spectra of C-2 monosubstituted norbornene and its derivatives are usually difficult to assign due to the anisotropy effect of norbornene ring and being a mixture of exo- and endo- isomers. Based on the preparation of configurationally pure C-2 substituted norbornene derivatives, this study assigned the ¹H and ¹³C NMR signals of exo-5-norbornene-2-carboxylic acid, endo-5-norbornene-2-carboxylic acid, exo-5-norbornene-2-methanol and endo-5-norbornene-2-methanol by combined use of ¹H NMR, DEPT135, ¹H-¹H COSY, ¹H-¹³C HMQC and ¹H-¹H NOESY spectroscopy, and corresponding coupling constants. The effects of norbornene derivatives' C-2 substituents and their configurations on ¹H NMR chemical shifts of the compunds were also investigated.