Atropoisomerism in phosphepines and azepines.
Free energy barriers to biaryl tropoinversion in metal complexes with tropos phosphepine and azepine ligands were determined by temperature-dependent (31)P NMR inversion-transfer experiments and line shape analysis of the temperature-dependent (1)H NMR spectra, respectively. The barrier in the PdCl(2) complex of the azepine ligand was found to be slightly higher than that of the corresponding free ligand. Studies of a tridentate azepine ligand suggested that configurational change takes place without prior decoordination from the metal.
Fjellander
Ester
E
KTH School of Chemical Science and Engineering, Department of Chemistry, SE 100 44 Stockholm, Sweden.
Szabó
Zoltán
Z
Moberg
Christina
C