Nucleophiles organometallic reagents

Asymmetric synthesis of amino acids.1 These lactones can serve as an optically active form of glycine for synthesis of either D- or L-amino acids. Thus (+ )-1 (or (—)-l) on radical bromination is converted into a single monobromide (2), which can be coupled with nucleophilic organometallic reagents, by either an SN1... 

The disconnection strategies summarised on p. 586 reveal that the nucleophilic organometallic reagents derived from alkyl halides (e.g. R MgX, RLi) require... 

Like other strong nucleophiles, organometallic reagents—RLi, RMgX, and R2CuLi—open epoxide rings to form alcohols. 

Usually, less nucleophilic organometallic reagents such as tin (26 or 27 ), zirconium (28 ) and cadmium have been used for selective transmetallation (equations 36 , 37 , 38 and 39 ). CgHjSiFs has been used to prepare (CgH5)2SbF from SbFs (equation 40) . 

Less nucleophilic organometallic reagents, such as derivatives of tin , zirconium lead and cadmium , have usually been used for selective transmetallation (equations 65 , 66 , 67 and 68 ). Enamines have also been used (equation 69) . 

Over the past two decades, many nucleophilic organometallic reagents... 

One possible retrosynthesis of a ketone TM is by disconnection at the carbonyl carbon. The carbonyl carbon used to be the electrophile (acid chloride or nitrile), and the other carbon was the nucleophile (organometallic reagent, or a benzene ring if it is an aromatic ketone TM). 

The same authors also used ESI-MS/MS to study an air-promoted oxidative Heck reaction between arylboronic acids and enamides as electron-rich olefins (Scheme 7.13) [29]. In addition to the conventional Mizoroki-Heck reaction of unsaturated compounds with organic halides or triflates as electrophiles, the use of nucleophilic organometallic reagents, such as organoboron compounds, has... 

The preparation and use of these nucleophilic organometallic reagents in the presence of electrophilic fluorinated olefins was a surprising result and prompted us to explore theoretical support for their stability. Upon calculating (at the ab initio level) deprotonation energies of trifluorovinyloxy substituted benzene and pyridine model compounds vs. the corresponding methyl ether, we found that perfluorovinyl... 

In Summary The carbonyl group in aldehydes and ketones can be attacked by carbon-based nucleophiles. Organometallic reagents give alcohols and cyanide gives cyanohydrins. 

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