New expeditions in polar organometallic chemistry

摘要

Since Frankland’s seminal discovery of ZnEt_2 in 1849, when he reacted elemental zinc with ethyl iodide in a sealed tube, polar organometallic reagents have become essential tools in the synthetic chemist’s toolbox. The longest servants amongst this family of compounds are organolithium and Grignard reagents, whose exceptionally high reactivity (due primarily to the large polarization of their metal–carbon bonds) makes them valuable reagents, capable of promoting numerous fundamental organic transformations, being in fact indispensable to any laboratory worldwide where synthetic chemistry is carried out. Despite their long-standing and ubiquitous utility, the true identities of many organometallic intermediates still remain unresolved and a matter of debate, while the ways of tuning their reactivity still attract widespread interest. Furthermore, studies on f-block chemistry, as well as new developments in the chemistry of the elements of other groups, such as 1, 2, 12 and 13, have made the family of polar organometallic reagents, and subsequently their applications, grow exponentially over the past ten or so years.