Conformational behaviour of medium-sized rings. Part 13. 5,18-Dihydro- and 5,11,12,18-tetrahydrotribenzo[b,f,j][1,4]diazacyclododecine-6,17-diones
作者:W. David Ollis、Julia Stephanidou Stephanatou、J. Fraser Stoddart
DOI:10.1039/p19820001715
日期:——
18-dimethyl-(7) and 5,18-dibenzyl-(8) derivatives of (6) adopt enantiomeric non-planar conformations with averaged C2 symmetry in solution. In the case of the two 5,18-dibenzyl derivatives (5) and (8), ring inversion is shown to be slow (ΔG‡= 20.4 and 21.1 kcal mol–1, respectively) on the 1H n.m.r. time scale at room temperature and probably involves propeller-like conformations (9a)⇌(9b) as the enantiomeric
不饱和(3)和饱和(6)的双内酰胺是由邻苯二胺与衍生自反式-苯乙烯-2,2'-二羧酸和联苄-2,2的双酰氯(1)和(2)缩合制得的分别为′-二羧酸。动态1 H nmr光谱表明(3)的5,18-二苄基衍生物(5)以及(6)的5,18-二甲基-(7)和5,18-二苄基-(8)衍生物采用对映体非-平面构象,溶液中平均C 2对称。在两个5,18二苄衍生物(5)和(8)的情况下,环反转被示出为是缓慢(Δ ģ ‡ = 20.4和21.1千卡摩尔-1分别)在1室温下的H nmr时间标度可能涉及螺旋桨状构象(9a)⇌(9b)作为对映体基态构象。饱和双内酰胺(6)的5,18-二甲基-(7)和-二苄基(8)衍生物均形成1:1的包合物,(7)与邻二甲苯和(8)与乙醇。