Conformational study of the 4,9-dihetero-(Z,Z)-cyclodeca-1,6-diene ring system; the mono- and di-benzo analogues
作者:E. Kleinpeter、J. Hartmann、W. Schroth
DOI:10.1002/mrc.1260280713
日期:1990.7
The dynamic 1H and 13C NMR spectra of a series of mono‐ and bis‐annelated 4,9‐dihetero‐(Z,Z)‐cyclodeca‐1,6‐dienes were obtained and are discussed with respect to ground‐state conformers and the barriers to ring inversion, and to the restricted rotation about exocyclic partial C,N double bonds. The ten‐membered rings are, with one exception, anancomeric chair conformers and interconvert via a combination
获得了一系列单-和双-退火 4,9-二杂-(Z,Z)-环癸-1,6-二烯的动态 1H 和 13C NMR 谱,并讨论了基态构象异构体和环反转的障碍,以及围绕环外部分 C,N 双键的受限旋转。除了一个例外,十元环是 anancomeric 椅型构象异构体,并通过单键旋转和键角弯曲的组合相互转换。根据存在的杂原子,获得了一系列降低环反转的势垒 S > NH > O。由于更大的分子内跨环 H,H 相互作用,Benzannelation 降低了相同动态过程的激活自由能。