Stereoisomerism, crystal structures, and dynamics of belt-shaped cyclonaphthylenes

For CaNAP, we manually examined and counted the possible isomeric structures in the 28 adoptable structures but made one mistake in the count

Zhe Sun; Takuya Suenaga; Parantap Sarkar; Sota Sato; Motoko Kotani; Hiroyuki Isobe

2016

Scholarcy highlights

  • The chemistry of hoop-shaped cycloarylenes is being enriched by increasing variations in the molecular structures
  • The belt-shaped structure with C2h panels gave rise to stereoisomerism originating from the facial orientations of the naphthylenes
  • The stereoisomerism was clarified with the aid of mathematics and revealed the complicated nature of the stereoisomerism of belt-shaped nanohoops
  • Structures of several stereoisomers with belt shapes were elucidated by crystallographic analyses, and comparison with theoretical energetics indicated that the crystal structure does not necessarily adopt the most stable conformation
  • For the present arylene panel of naphthylene, the diameter of 1.26 nm is the spectroscopic threshold that divides fluctuating nanohoops and rigid nanohoops. Another obvious structural factor that controls the structural rigidity is the size of the arylene panels: A chrysenylene nanohoop,-CC, with a nearly identical geometrical diameter of 1.27 nm, possessed an extreme rigidity and did not fluctuate for 2 months at 200 °C
  • Dynamics studies with nanohoops possessing various arylene panels are of fundamental interest to reveal the correlations between the hoop/ panel size with the rigidity in the future
  • We hope that the present study may stimulate further studies to deepen our understanding of the unique structural chemistry of nanohoops

Need more features? Save interactive summary cards to your Scholarcy Library.