Organocopper compounds, and

The synthesis of allenes from organocopper compounds and acetylenic acetates was... 

Other exchange reactions have been reported between organocopper compounds and mercuric halides 40, 73, 209). 

Together with dinuclear molybdenum dialkyldithiocarbamates, trinuclear dialkyldithiocarbamates have recently been introduced for lubricant applications, specifically for use in engine oils [48]. These molecules are based upon [Mo3S4]" and [MosSy] cores complexed by four dialkyldithiocarbamate ligands. It has been reported that these products decompose hydroperoxides more effectively than do dinuclear molybdenum dialkyldithiocarbamates. The patent literature discloses trinuclear molybdenum dialkyldithiocarbamates that are most effective as antioxidants when combined with radical scavengers such as organocopper compounds and diphenylamines [49]. 

Synthesis.— A review on organocopper compounds and organocuprates in synthesis has appeared these reagents are particularly useful for constructing olefins. Thus stereospecifically trisubstituted alkenes (381) are obtained by alkylation of vinylcopper reagents in the presence of triethyl phosphite and HMPA. The vinylcopper rea nts (382) are obtained by addition of acetylenes to a reagent prepared from R MgX and cupric bromide in ether at — 10 C. Alkylation occurs with retention of configuration... 

Intensive studies have been devoted to a mechanistic rationale of the conjugate addition of organocopper compounds and give a rather complex picture [141, 135, 136]. A simplified mechanistic model starts from dimeric lithium cuprates 131, wherein oxygen is assumed to coordinate to lithium and the carbon-carbon double bond to copper. The chelated cuprate 133, but also the nonchelated species 132 might function as intermediates for the formation of... 

FIGURE 15.48 Preparation of organocopper compounds and their reaction with acyl halides. 

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