separate causes of the twisted ring. Since the calculated (and observed) structure of 1,4-B4O2(OH)4 is planar but that of 1,4-B4S2(OH)4 is twisted, it is concluded that the inclusion of sulfur in the ring twists the structure by approximately 40°. By comparing the structures of 1,4-B4S2(OH)4 and 1,4-B4S2(NMe2)4 it has been determined that the twist caused by the NMe2 groups is around 30°.
1,4-B 4 S 2(NMe 2)4的结构已通过气相确定电子衍射和量子
化学计算,并与已知的固态结构进行比较。虽然这些结构相似,但具有扭曲的环几何形状[电子衍射它们是75.4(16)°],它们与1,4-B 4 O 2(OH)4的固态平面结构显着不同。使用量子
化学计算,研究了环中的O或S与OH或NMe 2作为取代基的组合,结果表明,有两个不同的成环原因。由于1,4-B 4 O 2(OH)4的计算(和观察到的)结构是平面的,但是1,4-B 4 S 2(OH)4的结构是扭曲的,因此可以得出结论:环将结构扭曲约40°。通过比较1,4-B 4的结构对于S 2(OH)4和1,4-B 4 S 2(NMe 2)4,已经确定由NMe 2基团引起的扭曲为约30°。