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Copper iodide catalyst

The coupling reactions with the benzoyl chloride and allyl iodide required the addition of 10% Cul as catalyst to yield the corresponding ketone and allyl derivatives. In the absence of copper iodide catalyst, the prementioned two electrophiles gave only low yields ofthe expected products. 1,2-Dibromoethane was used to remove the excess of magnesium when benzoyl chloride or ally iodide was used as electrophiles (entries 6 and 7), and it did not react with the Grignard reagents under the given reaction conditions. [Pg.196]

Alternative procedure. The following method utilises a trace of copper sulphate as a catalyst to increase the speed of the reaction in consequence, a weaker acid (acetic acid) may be employed and the extent of atmospheric oxidation of hydriodic acid reduced. Place 25.0 mL of 0.017M potassium dichromate in a 250 mL conical flask, add 5.0 mL of glacial acetic acid, 5 mL of 0.001M copper sulphate, and wash the sides of the flask with distilled water. Add 30 mL of 10 per cent potassium iodide solution, and titrate the iodine as liberated with the approximately 0.1M thiosulphate solution, introducing a little starch indicator towards the end. The titration may be completed in 3-4 minutes after the addition of the potassium iodide solution. Subtract 0.05 mL to allow for the iodine liberated by the copper sulphate catalyst. [Pg.393]

The reaction with ammonia or amines, which undoubtedly proceeds by the SnAt mechanism, is catalyzed by copper and nickel salts, though these are normally used only with rather unreactive halides. This reaction, with phase-transfer catalysis, has been used to synthesize triarylamines. Copper ion catalysts (especially cuprous oxide or iodide) also permit the Gabriel synthesis (10-61) to be... [Pg.864]

In 1988, Linstrumelle and Huynh used an all-palladium route to construct PAM 4 [21]. Reaction of 1,2-dibromobenzene with 2-methyl-3-butyn-2-ol in triethylamine at 60 °C afforded the monosubstituted product in 63 % yield along with 3% of the disubstituted material (Scheme 6). Alcohol 15 was then treated with aqueous sodium hydroxide and tetrakis(triphenylphosphine)palladium-copper(I) iodide catalysts under phase-transfer conditions, generating the terminal phenylacetylene in situ, which cyclotrimerized in 36% yield. Although there was no mention of the formation of higher cyclooligomers, it is likely that this reaction did produce these larger species, as is typically seen in Stephens-Castro coupling reactions [22]. [Pg.88]

Potassium tert-butoxide reacts with copper iodide to generate a copper / -butoxide species 98 (Scheme 29). Activation of the alkyne 94 by this copper catalyst (intermediate 96) allows the enolate attack to afford the cyclic... [Pg.312]

There is continued expansion in the use of metals as catalysts in substitution reactions. Copper iodide in the presence of /V./V -dimcthylcthylcncdiamine has been shown to be effective in the intramolecular substitution of aryl bromides carrying an o-l,3-dicarbonyl substituent reaction may involve either an oxygen centre or a carbon centre of the dicarbonyl moiety.26 The reaction of aryl halides with sodium trifluoroacetate in the presence of copper iodide may lead to the formation of the tri-fluoromethylated derivatives, possibly via CF3CuI as an intermediate.27 There have been theoretical calculations, PM3 and ab initio, on complexes formed from copper... [Pg.179]

Beletskaya has shown that the reaction of benzotriazoles with aryl halides catalyzed by a mixture of dppe (bis-(diphenylphosphino)ethane) and copper iodide or copper(II) carboxylates proceeds in good yield in DMF solvent and with a phase-transfer catalyst [142]. The mechanism of these reactions is unknown, and copper is known to catalyze such reactions. However, it was shown that both copper and palladium are required for these reactions to occur at the N-l position in high yields. Similar results were observed in aqueous solvent using aryliodonium salts as electrophile [143]. [Pg.225]

The coupling of terminal alkynes with aryl or vinyl halides under palladium catalysis is known as the Sonogashira reaction. This catalytic process requires the use of a palladium(0) complex, is performed in the presence of base, and generally uses copper iodide as a co-catalyst. One partner, the aryl or vinyl halide, is the same as in the Stille and Suzuki couplings but the other has hydrogen instead of tin or boron as the metal to be exchanged for palladium. [Pg.1330]

Phenylpropionic acid is conveniently prepared from cinnamic acid by electrolytic reduction (90%), by high-pressure hydrogenation over copper chromite catalyst (100%), or by reduction with phosphorus and potassium iodide in phosphoric acid (80%). ... [Pg.667]

An improvement in the Stille reaction was found to be the result of a synergistic effect between copper salts and fluoride. Adding copper iodide and cesium fluoride to the standard palladium catalyst resulted in a quantitative yield of 233 from 152 and 232 [86]. [Pg.216]

The catalyst used for this purpose by Teijin consists of thaliic tons in solution in hydrochloric add, while Halcon uses copper iodide and Kuraray employs palladium nitrate. [Pg.24]

Cross-coupling of terminal alkynes with aryl and vinyl halides are usually carried out in organic solvents, such as benzene, dimethylformamide or chloroform with a palladium-based catalyst and a base scavenger for the hydrogen halide. Copper iodide is a particularly effective co-catalyst allowing the reaction to proceed under mild conditions. [Pg.218]

Organometallic cross-coupling reactions provide a regiocontrolled method for the introduction of substituents to the indole ring. Palladium-catalzyed cross-coupling of 2-indolyldimethylsilanols have been utilized in the synthesis of 2-arylindoles <04OL3649>. For example, treatment of indole-2-silanol 206 and aryl iodides 207 with a palladium catalyst, copper iodide, and sodium f-butoxide provided 2-arylindoles 208. [Pg.132]

Copper (I) iodide Copper iodide (Cul) Copper monoiodide Copper(1 ) iodide Copper(l) iodide Cuprous iodide EINECS 231-674-6 EPA Pesticide Chemical Code 108301 HSDB 271 Hydro-Giene Natural marshite. Used as a feed additive, in table salt as source of dietary iodine, catalyst, in cloud seeding. Solid mpa 588-606° bp= 1290° d = 5.63 insoluble in all solvents. Atomergic Chemetals Blythe, Williams Ltd. Cerac Greet R.W. Co. Mitsui Toatsu Nihon Kagaku Sangyo Sigma-Aldrich Fine Chem. [Pg.165]

Aryl halides containing less reactive halogen can also be converted into sulfides by thiols if heavy-metal (lead, zinc, mercury) thiols are used at 225-230° 1-naphthyl, 2-naphthyl sulfide,301 1- and 2-naphthyl phenyl sulfide,302 and 1-and 2-naphthyl o-, m-, and p-tolyl sulfide303 have been obtained in this way. When the heavy-metal thiolates are too stable and do not react with aryl bromides even at 240°, the aryl sulfides can nevertheless often be prepared by a generally applicable reaction of aryl iodides with sodium thiolates under the influence of copper as catalyst.304... [Pg.639]


See other pages where Copper iodide catalyst is mentioned: [Pg.285]    [Pg.222]    [Pg.285]    [Pg.222]    [Pg.49]    [Pg.88]    [Pg.225]    [Pg.309]    [Pg.507]    [Pg.68]    [Pg.77]    [Pg.90]    [Pg.167]    [Pg.48]    [Pg.41]    [Pg.228]    [Pg.46]    [Pg.6]    [Pg.1330]    [Pg.128]    [Pg.136]    [Pg.1114]    [Pg.227]    [Pg.1332]    [Pg.1332]    [Pg.464]    [Pg.86]    [Pg.469]    [Pg.109]    [Pg.172]    [Pg.1330]   
See also in sourсe #XX -- [ Pg.3 , Pg.243 ]

See also in sourсe #XX -- [ Pg.3 , Pg.243 ]




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