The chemistry of the carbon-transition metal double and triple bond: Annual survey covering the year 2014

• Many examples were reported in 2014 where metal carbene/alkylidene complexes serve as catalysts and reactive intermediates for olefin metathesis, which is an important tool in polymer chemistry and organic synthesis.
• Several reports in 2014 featured metal carbyne/alkylidyne complexes as catalysts for alkyne metathesis, an emerging tool in organic synthesis and polymer chemistry.
• Many examples appeared in 2014 highlighting the facile generation of metal-carbene complexes from a variety of organic precursors, including alkynes, allenes, diazo compounds, triazoles, tosylhydrazones, and organolithium reagents, and have been instrumental in the design of reaction processes that lead to rapid gains in molecular complexity.
• In 2014 carbene complexes were reported for virtually every transition metal, and several examples of carbene complexes of lanthanides and actinides were reported as well.

This is a review of papers published in the year 2014 that focus on the synthesis, reactivity, or properties of compounds containing a carbon-transition metal double or triple bond.