Nuclear Magnetic Resonance Evidence for High Barrier of Conformational Inversion in Hexahydro-3,3,7,7-tetramethyl-1,2-oxazepine-5-one
作者:Roderick E. Wasylishen、Kenner C. Rice、Ulrich Weiss
DOI:10.1139/v75-057
日期:1975.2.1
Variable temperature proton n.m.r. spectra indicate an activation energy of 19.0 ± 0.5 kcal/mol for conformational equilibration in hexahydro-3,3,7,7-tetramethyl-1,2-oxazepine-5-one. It is suggested that the rate process involves slow conformational interconversion of the seven-membered ring and not slow inversion at the nitrogen atom. The synthesis of several related 1,2-oxazepines is described.
变温质子核磁共振谱表明,六氢-3,3,7,7-四甲基-1,2-氧氮杂-5-one 中构象平衡的活化能为 19.0 ± 0.5 kcal/mol。这表明速率过程涉及七元环的缓慢构象相互转换,而不是氮原子处的缓慢反转。描述了几种相关 1,2-氧氮杂卓的合成。