Copper mediation

Nucleophilic Reactions. Useful nucleophilic substitutions of halothiophenes are readily achieved in copper-mediated reactions. Of particular note is the ready conversion of 3-bromoderivatives to the corresponding 3-chloroderivatives with copper(I)chloride in hot /V, /V- dim ethyl form am i de (26). High yields of alkoxythiophenes are obtained from bromo- and iodothiophenes on reaction with sodium alkoxide in the appropriate alcohol, and catalyzed by copper(II) oxide, a trace of potassium iodide, and in more recent years a phase-transfer catalyst (27). 

The true, all-aromatic system (see 18, below) described by Kime and Norymberski is unusual in the sense that all of the ether linkages bridge aromatic carbons ". Synthesis of 18, therefore, required extensive use of copper mediated coupling reactions. As expected for such reactions, yields were generally low. The aromatics such as 18 were ineffective at binding either alkali metal or ammonium cations ". ... 

Copper-mediated coupling of the aryl iodide derived from l,3-bis(2-hydroxy-hexafluoroisopropyl)benzene with perfluorooctyl iodide gives the desired compound as a dimethyl sulfoxide (DMSO) complex [166] (equation 143) Even bromoarenes can be coupled [167] (equation 144)... 

Copper-mediated Addition and Substitution Reactions of Extended Multiple Bond Systems... 

Copper-mediated Addition Reactions to Extended Michael Acceptors... 

Tlianks to tlieir ambident cliaracter, acceptor-substituted dienes can provide seveta isomeric products in copper-mediated Midiael additions, tlierefore making i pariicular impotLant to control not only tlie regiosdectivity but also tlie steteose lectivity of tliese transfotenations iSdieme 4.1). 

Copper-mediated Substitution Reactions of Extended Substrates... 

Copper-mediated Diastereoselective Conjugate Addition and Allylic Substitution Reactions... 

Copper-mediated or copper-catalyzed substitution teactiotis cati be perfotnied oti a tiLitiiber of different substrates fSclietiie 8.1). Stoicliiometric otgatiocopper reagents... 

As discussed in CbapL 6, copper-mediated diasteteoselective addition and substitution reactions ate well studied metliods for the construction of chiral centers in organic molecules. Tlie development of coppet-mediated enantioselective substitution reactions, however, is still at an early stage. 

Reaction between Cy symmetric diols and a,/ -unsaturated aldeliydes yield cliiral ediylenic acetals diat undergo copper-mediated substitution reactions. Widi aiyl or... 

Copper-Mediated Synthesis of Natural and Unnatural Products... 

Conjugate addition [2] to Midiael acceptors is die most important and usefid reaction in orgatiocopper diemistiy, and die reaction is ofien used as die key step in die syndiesis of numerous natural and unnatural products. Perhaps one of die most efficient methods for die syndiesis of quaternary carbon centers is organo-copper-mediated conjugate addidon to /, / -disubstituted enones. 

As described above, many copper-mediated reactions play important roles in tlie syntlieses of natural and unnatural products. To date natural product syntlieses using organocoppet reagents have beeti accomplisbed, and w ill undoubtedly be increasing greatly from now on. 

The Roles of Cluster Structure in Copper-mediated Reactions... 

Mechanisms of Copper-mediated Addition and CiAbstitiAtion Reactions... 

Sandman, G. Boger, P. (1980). Copper mediated lipid peroxidation processes in photosynthetic membranes. Plant Physiology, 66, 797-800. 

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