Metal groups allyl halides

Many methods have been reported for the addition of allylic groups, including allyltrialkyltin compounds" (in the presence of BF3-etherate), as well as other allylic metal compounds." Allylic alcohols and homo allylic alcohols add to aldehydes in the presence of Sn(OT02 " For allylic halides, both activated... 

There are few reports of oxidative addition to zerovalent transition metals under mild conditions three reports involving group 10 elements have appeared. Fischer and Burger reported the preparation of aTT -allylpalladium complex by the reaction of palladium sponge with allyl bromide(63). The Grignard-type addition of allyl halides to aldehydes has been carried out by reacting allylic halides with cobalt or nickel metal prepared by reduction of cobalt or nickel halides with manganese/iron alloy-thiourea(64). 

When Me3SiSnBu3 is treated with CsF, the fluoride anion should coordinate to the silyl group and not the stannyl group to produce a hypervalent silicate, and as a result, a stannyl anion would be generated.282 The stannyl anion reacts with vinyl iodide to produce a vinyl anion via a halogen-metal exchange and it reacts with the carbonyl group intramolecularly (Equation (113)). Aryl halides or allyl halides are also used in similar cyclizations.283,284... 

Attempts to bring about cross coupling of different allylic halides invariably led to mixtures suggesting exchange of the allylic units before coupling. This problem in synthesis is better solved by cross coupling of an allylic halide and an allylic derivative of a main group metal. However, electrophilic alkylation of )) -allyl-NiBr dimers by simple alkyl halides is successfiil (equations 130 and 131). 

Allylmagnesium halide and lithio reagents are available from allyl halides by lithiation and Mg reaction techniques. These active reagents combine with binary or complex transition-metal halides to form transition-metal-allyl complexes, including both homoleptic and ligand-substituted tj -allyl complexes with substituted and unsubstituted allyl groups. 

Oxidative addition of the carbon-halogen bond is a well-documented reaction for Group 10 transition metal complexes, but it is relatively limited for ruthenium. The example given here involves the reversible oxidative addition of allyl halide to RuCp(CO)2X to produce RuCp(p -allyl)X2 [78]. Oxidative addition of allyl halide to a Ru(0) complex Ru(l,5-COD)(l,3,5-COT) is also reported, but the product yield was poor [79]. Nevertheless, a catalytic Heck-type alkenylation of bromostyrene with methyl acrylate by Ru(l,5-COD)(l,3,5-COT) proceeded smoothly [80]. A cross-coupling reaction of alkenyl halide with Grignard reagents or alkyl lithium also pro-... 

In 1960 several groups of workers developed a route to the parent complex, TT-allylcobalt tricarbonyl (VII) 122, 123, 170) and also to tt-allylmanganese tetracarbonyl (VIII) 14S, 170). These syntheses were based on reactions of appropriate metal carbonyl anions with allyl halides as shown below. 

Group 6 pentacarbonyl acetato complexes have been also found to undergo addition of alkyl halides (Mel) to produce alkyl acetates and the pentacarbonyl halide metal complex. When allyl halides are used instead of alkyl halides, an oxidative addition product is formed, which contains the allyl, halide, and acetate ligands bonded to the metal. 

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