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Direct arylations tricyclohexylphosphine

A similar general method for the rhodium-catalyzed direct coupling of benzimidazoles with aryl bromides or iodides has also been developed under microwave-assisted conditions, and it has shown to provide rapid access to medicinally relevant compounds. Both electron-rich and electron-poor aryl iodides were observed to couple with tricyclohexylphosphine. The desired... [Pg.100]

The carbonylation of chloroarenes has been described by Alper and Grushin [27] and Jenner and Bentaleb [28], While the former showed that square-planar complexes of divalent palladium, [ L2PdCl2], where L = tertiary phosphine, are active catalysts for the biphasic carbonylation of aromatic halides, including chloroarenes (when L = tricyclohexylphosphine), to the corresponding carboxylic acids, the latter demonstrated that chloroarenes can be converted into aromatic acids via catalytic reaction with aqueous methyl formate under biphasic conditions. [ PdCl2(PCy3)2] was the most efficient catalyst. The addition of [ Ru3(CO)12] and ammonium formate improved yield and selectivity of the carbonylation reaction. The mechanism should involve oxidative addition of the C—Cl bond to a zero-valent Pd species followed by CO insertion. However, the palladium catalyst may also directly activate methyl formate. Compared to other carbonylations of aryl-Hal compounds the procedure is quite convenient (no solvent, no initial pressurization) [27]. [Pg.503]

Direct catalytic methods for C2 arylations have also been developed. An excess of diphenylzinc (3 equiv) can act as an aryl donor in the presence of a catal)4ic system bis(cyclooctadiene)nickel(0)/tricyclohexylphosphine (eq 30). ... [Pg.563]


See other pages where Direct arylations tricyclohexylphosphine is mentioned: [Pg.61]    [Pg.692]    [Pg.76]    [Pg.193]    [Pg.242]   
See also in sourсe #XX -- [ Pg.693 ]




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Aryl direct arylations

Arylation direct arylations

Arylations tricyclohexylphosphine

Direct arylation

Direct arylations

Tricyclohexylphosphines

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