In case of conjugated esters, greater reactivity observed when RCu∙BF3 is as the organocopper reagent
Examples:
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G. H. Posner, Organic. React. 1972,19. |
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K. C. Nicolaou, M. R. Pavia, S. P. Seitz, J. Am. Chem. Soc. 1982, 104, 2027. |
3.3.1.4 Reactions with Aldehydes and Ketones
Organocuprates react with aldehydes to give alcohols in high yield (Scheme 8). In the presence of chlorotrimethylsilane, the corresponding siliylenol ethers can be obtained.
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Scheme 8 |
The reaction of ketones with organocuprates is very sluggish. However, the reaction takes place conveniently in the presence of chlorotrimethylsilane (Scheme 9).
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Scheme 9 |