ChemInform Abstract: Conformational Analysis of Dioxa[2.2]orthocyclophanes.

✍ Scribed by H. KUREBAYASHI; T. MINE; K. HARADA; S. USUI; T. OKAJIMA; Y. FUKAZAWA

• Publisher: John Wiley and Sons
• Year: 2010
• Weight: 26 KB
• Volume: 30
• Category: Article
• ISSN: 0931-7597
• DOI: 10.1002/chin.199909030

✦ Synopsis

Conformational Analysis of Dioxa[2.2]orthocyclophanes.

-A conformational analysis of compounds (I), (II), and (III) is performed. NMR measurements do not allow to identify the preferred structures of (I) and (II). Molecular mechanics calculation on (Ia) show the following order of steric energy: twist boat ¡ screw ¡ chair conformation. Semiempirical and ab initio calculations give similar results. X-ray crystallographic studies show that compounds (Ib) and (II) adopt the twist boat conformation whereas (III) exists in the screw form. -(KUREBAYASHI, H.;