"Figure Eight" Cyclooctapyrroles: Enantiomeric Separation and Determination of the Absolute Configuration of a Binuclear Metal Complex.
The hypothesized racemate separation of cyclooctapyrroles with chiral figure eight conformations-and of metal complexes derived from these ligands-has been realized. The cyclooctapyrrole 1 (as hexadecaethyl derivative), which according to NMR analysis exhibits restricted mobility, and its binuclear palladium and copper complexes could be separated into stable enantiomers by preparative chromatography on a chiral phase. In the case of the palladium complex and the free ligand 1 it was also possible to determine the absolute configuration of the enantiomers.
Wernerdagger
A
Institut für Organische Chemie der Universität, Währinger Strasse 38, A-1090 Wien (Austria).
Michels
M
Zander
L
Lex
J
Vogel
E