Carboxylates bridging modes

Acetate remains the classical carboxylate ligand, with the capacity to bind in monodentate bidentate chelate (/i2), or bridging modes. Whereas early chemistry featured simple fii... 

Fig. 9. Potential carboxylate binding modes. The modes shown on the top row are considered explicitly in developing LFMM parameters although anti-anti and anti-syn bridging modes are within the scope of...

Carboxylate anions are versatile ligands that are found in a variety of coordination modes including unidentate, chelate, and a number of bis(monodentate) bridging modes.1 Such versatility makes the chemistry of carboxylate complexes particularly interesting. It is now also apparent that the diverse catalytic activity shown by many metal carboxylates may be rationalized in terms of the chemistry of the carboxylato ligand.2 In general though, few rational syntheses of metal carboxylates are known.1 This... 

Carbamate (R2NC02 ) complexes are similar electronically and structurally to monocarboxylate complexes, although they are not as accessible synthetically and are generally less stable. Unidentate, chelate, and bridging coordination modes have been observed, although the number of bridging modes found to date is less than that known for carboxylates. Syn-syn bridging is the most common, and bimetallic paddlewheel type structures (53) are known. 

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