Organometallic chemistry Stille coupling

NBS as a Ligand in Organometallic Chemistry. Bromo-bis(triphenylphosphine)(lV-succinimide)palladium(II) has been reported as a novel catalyst for Stille cross-coupling reactions. ... 

Organometallic chemistry has been a popular subject for the Nobel prize committee. In 1912 Grignard (Mg) won the award, in 1973 Wilkinson and Fischer for sandwich compounds (such as ferrocene), in 2005 Chauvin, Grubbs, and Schrock for alkene metathesis, and in 2010 Fleck, Negishi, and Suzuki (Stille had died in 1989) for transition-metal catalysed couplings. 

To date, catalytic applications of NHC-Fe systems are still scarce and do not reflect the full potential of this cheap, abundant and non-toxic metal that shows great promise for the formation of carbon-carbon bonds via cross-coupling reactions. Recourse to ill-defined species generated in situ and difficulties in understanding the intimate nature of reaction mechanisms do not ease the development of organo iron catalysis. Support from the related field of iron biocatalysis and recent discoveries in organometallic chemistry are expected to provide help and inspiration for further advances. 

Carbon-carbon bond formation is fundamental to all of organic chemistry. Nucleophilic displacement is still the basis for most of what we do, but over the past thirty years radical addition and organometallic coupling have both been brought to a level of practical importance. 

As far as catalysis is concerned it is already benefiting from new developments such as supercritical fluids, ionic liquids, sol-gel technology, solid phase reactions, parallel and combinatorial chemistry and some of these can be coupled to microwave irradiation. Already a number of very efficient organometallic (mainly iridimn based) catalysts have been produced although we are still some way from the acid, base situation where tritia-tion (or detritiation) rates can be estimated from a knowledge of acid-base strengths. 

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