Cyanobis dimethylphenylsilyl -cuprate

Physical Data relatively stable reagent at rt usually prepared in situ at 0 °C. 

Preparative Methods prepared by adding 0.5 equiv of dry copper(I) cyanide to dimethylphenylsilyllithium in THF (eq 1), which in turn is generated from chlorodimethylphenyl-silane and lithium metal. Analogous bis(trimethylsilyl)cyano-cuprates are prepared in a similar manner. 

More detail for the preparation of this and related reagents may be found in Fleming, I. In Organocopper Reagents A Practical Approach, Taylor, R. J. K., Eld. OUP Oxford, 1994 Chapter 12, pp 257-292. 

Handling, Storage, and Precautions cannot be stored or isolated. Care must be taken to avoid oxygen and moisture in the reaction system. Use in a fume hood. 

Structure and Properties of the Reagent. Low-temperature Si, C, and H NMR spectroscopic techniques have been used to probe the nature of these higher-order cuprates. These studies showed conclusively the facile dissociation-reassociation of ligands on copper. In the presence of methyllithium, dimethylphenylsilyllithium, and copper(I) cyanide, a mixed metallocuprate is formed (eq 2). The metallocuprate (2) preferentially transfers the dimethylphenylsilyl group to enones and 1-alkynes. 

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Eor reviews on silycopper reagents see reference 6 and (a) dilithium cyanobis(dimethylphenylsilyl)cuprate J. P. Marino, D. P. Holub, in Encyclopedia of Reagents for Organic Synthesis, L. A. Paquette (Ed.), Wiley, Chichester, 1995, Vol. 3, p. 1952. (b) lithium cyano(dimethylphenylsilyl)-cuprate Idem, Ibid, Vol. 5, p. 3069. 

Related Reagents. Dilithium Cyanobis(dimethylphenylsilyl) cuprate Dimethylphenylsilyllithium Dimethylphenylsilyl(me-... 

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