This book is aimed at graduate students and research workers in aU branches of ohemistry, who wish to gain insight into what continues'to be one of the fastest growing areas of the subject. Aonding to a metal center may stabilize a ligand towards some reagents, activate it towards others, or modify its chemical behavior in more subtle ways. AU these effects have their uses, and aU invite understanding in terms of mechanism. Thus mechanistic insight is linked to control of reaction pathways. The detailed working out of this relationship provides the central theme of the book. The effect of the metal may be electronic or steric, and may involve the energy or the entropy of activation. It may depend on changes induced in the initial state of the ligand, or on those that only arise further along the reaction pathway. It may involve one coordination site or several, and the effects may be more, or less, specific to the metal involved and more, or less, amenable to control through the other Jigands. These remarks apply equaUy strongly to the carbon-bound ligands which occupy the major part of this work, and to those attached by other atoms. Thus the reactions discussed here are relevant in such diverse areas as bulk homogeneous catalysis, stereoselective stoichiometric synthesis, and bioinorganic chemistry.

This, the second and final volume of Reactions of Coordinated Ligands, describes the chemistry of ligands bound through non-carbon atoms, and of coordinated carbon dioxide. As before, emphasis is on the underlying mechanisms, which provide a unity of understanding for superficially disparate processes. The wide range of topics covered illustrates well both the versatility and the usefulness of coordination chemistry in the controlled activation of ligands. Looking to the future, carbon dioxide is the feedstock of last resort. The homogeneous reduction of dinitrogen to ammonia now seems unlikely to replace the Haber process, but solution reactions also lead to more complex, varied, and valuable products. Nitrogen monoxide, a "non innocent" ligand, impinges as pollutant and reagent. Its rich chemistry stems from its linked roles as three-electron donor, and as extremely powerful -acceptor. In the hydrolysis and condensation of complexed amides, esters etc., metals act both as templates and as tunable and poly functional Lewis acids. Here the control of hydrophobic and steric interactions begins to model the subtle mechanisms of biological specificity. Finally, phosphorus and sulfur are imporant both as ligand atoms in themselves, and as anchors for other functionalities. I would like to thank all those who have been involved in the writing and production of this work, and also my colleagues old and new, at Glasgow and the University of North Texas, for their support. Paul S. Braterman v CONTENTS 1. Reactions of Coordinated Carbon Dioxide 1 J. D. Miller 1."