Organolithiums transmetalation reactions

Organolithium and -magnesium compounds. Compared with extensive studies carried out on the Ni-catalyzed transmetallation reaction of Grignard reagents[43I,432], few examples of the Pd-catalyzed reactions of Mg are... 

Certain heterylgermanes undergo transmetallation reactions with organolithium compounds. This is shown in reaction 10, as well as the effectiveness of the various organolithium compounds121. 

TRANSMETALLATION REACTIONS 4.8.1 Lithium-tellurium exchange generation of organolithium reagents... 

Having in mind the fact that lithium is the most electropositive metal among those with wide synthetic applications (Li, Mg, Zn, Cd, Cu), the preparation of an organolithium compound formally represents the access to any other of such classes of organometallic compounds by a transmetallation reaction (Scheme 88).240... 

The reaction of organolithiums or organomagnesium halide reagents with gold halides proceeds similarly to the copper halides in a 1 1 ratio. Their phosphine complexes can be isolated and characterized. In a 2 1 ratio, the transmetallation reaction is followed by ate complexation to form organoaurate complexes ... 

Mi) Supplementary References. The transmetallation reactions of organolithiums and organoaluminums are extensively reviewed. The preparation of organotransitiop-metal compounds via transmetallation is discussed in various monographs dealing with Ti, Zr and Hf Cr Ni Pd and Pt. The preparation of organoactinide compounds via transmetallation is discussed in reviews . ... 

The detailed discussion of transmetallation reactions with organolithium compounds (1, XM = RLi), and coupling reactions (5) in the presence of transition metal catalysts (particularly the Stille reactions) is deferred until Sections 22.1 and 22.2. 

Arylsilver compounds ArAg, where the aryl group carries one or two substituents containing a heteroatom, have been obtained by transmetallation reactions of silver bromide with the corresponding organolithium compounds 2-[(dimethylamino)methyl]phenyl silver (17)70, (2,6-dimethoxyphenyl)silver (18)70 71 and (2,4,6-trimethoxyphenyl)silver (19)70. The compounds show an enhanced thermal stability with decomposition temperatures well above 150 °C. 

Lithium-Zinc Transmetallation. The transmetallation reaction of organolithium reagents with zinc salts is a more... 

The organolithium compounds formed by the reaction shown in eq. (3.1 ) tend to react with hydrocarbon halides by the Wurts coupling reaction and the yields of organolithium compounds are low if the resultant organolithium compounds are very reactive compounds such as allylithium or benzyllithium. Hence, for these reactions, transmetalation reactions, as described below are used. Therefore, this reaction is used for production of organolithium compounds having relatively low reactivity such as alkyllithiums, vinyllithiums and aryllithiums [14—20]. 

Transmetalation of lithium or organolithium compounds with various kinds of organometallic compounds proceeds as described above and shown in eqs. (3.4) and (3.5). In particular, the transmetalation with organotin compounds is widely utilized for organic syntheses as shown in eq. (3.30) [75—77]. The transmetalation reaction of tin and lithium as shown in eq. (3.30) is in an equilibrium state and if R is an alkenyl, an alkynyl, an allyl and substituents having a hetero atom, the reaction easily proceeds. If R is a saturated alkyl group, the reaction is difficult [75,76]. 

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