Cyclic-tri(N-methyl-meta-benzamide)s: substituent effects on the bowl-shaped conformation in the crystal and solution states
作者:Hiroki Kakuta、Isao Azumaya、Hyuma Masu、Mio Matsumura、Kentaro Yamaguchi、Hiroyuki Kagechika、Aya Tanatani
DOI:10.1016/j.tet.2010.08.049
日期:2010.10
Cyclic trimers of 3-(N-alkylamino)benzoic acid (calix[3]amides) with various substituents at the meta position of the phenyl rings were synthesized and the effects of the substituents on the crystal structures and energy profiles in solution were examined. The calixamides existed in a syn conformation in the crystal state, and this was also the major conformation in solution, especially in polar solvents
合成了在苯环的间位具有多个取代基的3-(N-烷基氨基)苯甲酸环状三聚体(杯[3]酰胺),研究了取代基对溶液中晶体结构和能谱的影响。杯氨酰胺以顺式构型以结晶状态存在,并且这也是溶液中的主要构型,尤其是在极性溶剂中。取代基(12.7-14.0 kcal / mol)对溶液中顺式和反式构象异构体之间的能垒没有显着影响。上的温度依赖性的取代基的效果顺/反讨论比。