Stereochemical Non-rigidity (Internal Rotation and Metallotropy) of Organic Derivatives of Transition Metals Investigated by Nuclear Magnetic Resonance Spectroscopy

Types of stereochemical non-rigidity of organic derivatives of transition metals, which have been widely studied by nuclear magnetic resonance during recent years, are classified. Two types of process – internal rotation in complexes of transition metals and intramolecular transfers of metal-containing groups (metallotropy) – are examined in greater detail. The discussion of the most characteristic structural situations met in π-complexes of transition metals covers not only the dynamic processes already observed by the n.m.r. method but also examples of compounds for which such processes have not yet been observed but may in principle be found. A list of 256 references is included.