A pentacycloundecane dimer

Abstract

The title compound, 6,6‐(3,6‐diprop‐2‐enyl­penta­cyclo­[6.2.1.02,7.04,10.05,9]­undecane‐3,6‐diyl­di­oxy)­penta­cyclo­[6.2.1.02,7.04,10.05,9]­undecan‐3‐one, C28H30O3, is a penta­cyclo­undecane dimer. The mol­ecule is chiral and contains two polycyclic penta­cyclo­undecane cage units. Both enanti­omers are present in the crystal structure. In the mol­ecule, certain C—C bond lengths deviate from the normal value, with both short and long bonds present.

NMR assignments of a di‐pentacyclo‐undecane cyclic ether

“…Fortunately, the product was crystalline and the X-ray structure of the product 5 was determined. 18 Note that the crystal structure contained both enantiomers in the unit cell. One of the enantiomers is depicted in Fig.…”

“…Owing to major overlap of the proton signals and some overlap of the carbon signals, it was decided to first elucidate the NMR spectra of the two PCU 'fragments' 2 and 6, which represent similar structural features when compared to the cyclic ether 5 (Figs 3 and 4). The same numbering system used for the X-ray structure 18 of the cyclic ether is used in this report. The elucidation of the analogues (2 and 6, Tables 1 and 2, Figs 3 and 4) is quite trivial and the NMR data are presented below for comparison purposes.…”