Halides with organometallics

Coupling Reactions of Aryl-Alkenyl Halides with Organometallic Reagents and Related Nucleophiles50... 

The general mechanism of coupling reactions of aryl-alkenyl halides with organometallic reagents and nucleophiles is shown in Fig. 9.4. It contains (a) oxidative addition of aryl-alkenyl halides to zero-valent transition metal catalysts such as Pd(0), (b) transmetallation of organometallic reagents to transition metal complexes, and (c) reductive elimination of coupled product with the regeneration of the zero-valent transition metal catalyst. 

Coupling of alkyl halides with organometallic reagents other than... 

Coupling of unsaturated halides with organometallic reagents... 

Metallation of alkyl or aryl halides with organometallic compounds... 

It is clear that the successful application of these C-glycosylations to the D-aldofuranose series, by treatment of the appropriate per-O-acylaldofuranosyl halides with organometallic reagents, could lead to synthetically useful C-glycosyl derivatives. Zhdanov and co-... 

Reaction of Glycosyl Halides with Organometallics and Carbanions... 

The Reaction of Alkyl Halides with Organometallic Reagents 265 Alkyl-de-halogenation... 

Reduction of unsaturated halides 0-78 Reduction of allylic alcohols 0-82 Reductive cleavage of enamines 0-86 Coupling of vinylic halides 0-87 Coupling of unsaturated halides with organometallic reagents 0-88 Coupling of allylic halides, tosylates, or acetates... 

The most synthetically useful reaction of nucleophilic tellurium consists in the reaction of organotellurium halides with organometallics. This reaction was systematically studied for the first time by Petragnani several years ago.80 In recent years, it has been used to prepare a number of tellurium-containing organic substrates. The general route is shown in Scheme 57. 

Another, mechanistically closely related reaction is the cross-coupling reaction of aryl, benzyl, vinyl, or allyl halides with organometallic coupling reactions, such as Grignard reagents or, preferably, less reducing organometallics such as tin compounds or boronic acids RB(OH)2 the latter allow the reaction to be conducted even in aqueous media.83 The principal reaction steps are ... 

Other preparative routes to aluminum alkyls include reaction of aluminum halides with organometallic reagents such as lithium alkyls (Equation (3)). 

W. J. Considine Alkylation (arylation) of metal halides with organometallics, pp. 4-11 (11). 

The coupling of alkyl halides with organometallic compounds is the only one of these methods in which carbon-carbon bonds are formed and a new, bigger carbon skeleton is generated. 

These Ziegler-Natta catalysts are complexes of transition metal halides with organometallic compounds typically, triethylaluminum-titanium trichloride. 

Palladium-catalyzed cross-coupling of acyl halides with organometallic reagents of zinc and tin is a convenient synthetic route to ketones and aldehydes. Typical examples are shown in eq (85) and (86) [116,117]. 

Pd-catalyzed coupling of acyl halides with organometallic reagents is a useful synthetic method of ketones. The alkylzinc reagent 127, prepared from the corresponding alkyl iodide with Zn/Cu couple, was coupled with the acid chloride 128 to give the ketone 129 in 50 % yield and used for the total synthesis of amphidinolide T14 [55]. 

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