Organohthium reagents

The formation of a Gngnard reagent is analogous to that of organohthium reagents except that each magnesium atom can participate m two separate one electron transfer steps... 

Alkenyllithium compounds can also be prepared by metaUation of alkenes, particularly when alkenyl hydrogens are rendered acidic by an a-substituent (equation 22). Transmetallation of alkenyl stannanes with organohthium reagents gives alkenyUithium compounds with retention of alkene stereochemistry (equation 23). Tin lithium fransmet-allation has been used to prepare 1,4-dihthio-l,3-butadiene. Monosubstituted alkenylhthium compounds RHC=CHLi, can also be prepared from the corresponding diorganotel-luride, RHC=CHTeBu, by reaction with butylhthium in... 

The Addition of Grignard Reagents and Organohthium Reagents to Aldehydes and Ketones... 

Mechanisms for the addition of organohthium reagents have been investigated much less. Addition of a cryptand that binds Li inhibited the normal addition reaction, showing that the lithium is necessary for the reaction to take place. There is general agreement that the mechanism leading to reduction " is usually as follows ... 

Cuprates have also been shown to be effective nucleophiles. Cuprates are formed when copper salts are added to organohthium reagents [89]. As shown in Scheme 6.56, these reagents, when added to anhydro sugars, readily form new carbon-carbon bonds with ring opening of the epoxide and... 

Maeda. H., Takahashi. K.. and Ohmori. H., Reactions of acyl tribulylphosphonium chlorides and dialkyl acylphosphonates with Grignard and organohthium reagents. Tetrahedron, 54, 12233, 1998. 

Ivanov, D., Vassilev, G., and Panayotov, L, Syntheses and reactions of organohthium reagents derived from weakly acidic C-H compounds. Synthesis, 83, 1975. 

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