Title screen

[References: p. 579 (55 tit.)]

Olefin metathesis is a transition metal-mediated transformation that rearranges the carbon atoms of the carbon–carbon double bond of olefins. This reaction has become one of the most important and powerful reactions. Therefore development of new, well-defined, highly active and selective catalysts is very desirable and a valuable goal. This mini-review mainly introduces the development of ruthenium catalysts in olefin metathesis highlighting oxygen-chelated indenylidene ruthenium catalysts. Applying an alkoxyl group on the indenylidene ligand fragment can generate the Ru[BOND]O chelating bond. Additionally, various modifications of the ligand as well as the catalytic activity for ring-closing metathesis reaction and selectivity of cross metathesis reaction are overviewed. Finally, the perspectives on the development of new catalysts are summarized.