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Carbonyl bromide chloride metals

Mediated by Tin. In 1983, Nokami et al. observed an acceleration of the reaction rate during the allylation of carbonyl compounds with diallyltin dibromide in ether through the addition of water to the reaction mixture.74 In one case, by the use of a 1 1 mixture of ether/water as solvent, benzaldehyde was allylated in 75% yield in 1.5 h, while the same reaction gave only less than 50% yield in a variety of other organic solvents such as ether, benzene, or ethyl acetate, even after a reaction time of 10 h. The reaction was equally successful with a combination of allyl bromide, tin metal, and a catalytic amount of hydrobromic acid. In the latter case, the addition of metallic aluminum powder or foil to the reaction mixture dramatically improved the yield of the product. The use of allyl chloride for such a reaction,... [Pg.229]

Anion-exchange resins can be used as reagents.242 They are commercially available with acetate, borohydride, bromide, chloride, dichromate, iodide, and periodate anions. Metal carbonyl-containing anions such as Co(CO)7,... [Pg.115]

TT-Allylpalladium chloride (36) reacts with the nucleophiles, generating Pd(0). whereas tr-allylnickel chloride (37) and allylmagnesium bromide (38) reacts with electrophiles (carbonyl), generating Ni(II) and Mg(II). Therefore, it is understandable that the Grignard reaction cannot be carried out with a catalytic amount of Mg, whereas the catalytic reaction is possible with the regeneration of an active Pd(0) catalyst, Pd is a noble metal and Pd(0) is more stable than Pd(II). The carbon-metal bonds of some transition metals such as Ni and Co react with nucleophiles and their reactions can be carried out catalytic ally, but not always. In this respect, Pd is very unique. [Pg.17]

The methods of preparation of ferrocene have been reviewed by Pauson and by Fischer. Ferrocene has been made by the reaction of ferric chloride with cyclopentadienylmagnesium bromide, by the direct thermal reaction of cyclopentadiene with iron metal, by the direct interaction of cyclopentadiene with iron carbonyl, by the reaction of ferrous chloride with cyclopentadiene in the presence of organic bases such as diethyl-amine, by the reaction of ferrous chloride with sodium cyclo-[lentadienide in liquid ammonia, and from cyclopentadiene and... [Pg.33]

Acetone Alkali cyanides, hydrides, metals Aluminum borohydride, carbide, hydride nitride Benzoyl chloride Boron compounds Carbonyls Chlorine Cyanogen Cyanogen bromide Cyanogen chloride... [Pg.1027]

Carbonylation of vinyl halides. These two reagents react to form tetracar-bonylmethylcobalt, CH3Co(CO)4. In the presence of hydroxide ion, this organo-metallic and carbon monoxide convert vinyl bromides or chlorides into the corresponding carboxylic acids. [Pg.118]

The coupling reaction of a-keto esters with allyl, propargyl, and allenyl halides using indium metal in aqueous solvents affords a-hydroxy-y,<5-unsaturated esters (Equation (28)).197,198 1,3-Dicarbonyl compounds undergo efficient carbonyl allylation reactions in an aqueous medium through a Barbier-type reaction (Equation (29)). The reaction is general and a variety of 1,3-dicarbonyls has been alkylated using allyl bromide or allyl chloride in conjunction with indium.199... [Pg.675]

Although Smh is more chemoselective than traditional dissolving metal reagents, it does react with sulfoxides, epoxides, the conjugated double bonds of unsaturated ketones, aldehydes and esters, alkyl bromides, iodides and p-toluenesulfonates. It does not, however, reduce carboxylic acids, esters, phosphine oxides or alkyl chlorides. In common with most dissolving metal systems, ketones with an a-hetero substituent suffer loss of the substituent rather than reduction of the carbonyl group. ... [Pg.115]

The catalytic carbonylation of allyl chloride to form 3-butenoate proceeds through a 7r-allyl complex which is formed by the oxidative addition of allyl chloride to metallic palladium. The 7r-allyl complex formation has been reported by Fischer and Burger (4) with allyl bromide and palladium as a supporting evidence. The carbonylation then proceeds by the insertion of carbon monoxide as before. [Pg.159]


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See also in sourсe #XX -- [ Pg.737 ]




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Bromides carbonylation

Carbonyl bromide

Carbonyl chlorid

Carbonyl chloride

Chlorides carbonylation

Chlorides metal

Metal bromides

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