Cyano dimethylphenylsilyl cuprate

Preparative Methods the title reagent (1), as well as lithium cyano (trimethylsilyl)cuprate [81802-36-0], can be prepared from the corresponding silyllithium species and 1 equiv copper(I) cyanide in ether or THF at —78 to —5°C the precursor silyllithium (2) is generated by the reaction of chlorodimethylphenylsilane with lithium metal in THF or ether (eq 1). 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., Ed. OUP Oxford, 1994 Chapter 12, pp 257-292. 

The analogous trimethylsilylcuprate (3) adds to ethyl-2-butynoate at 0 °C to give a mixture of stereoisomers, while the higher-order species reacts at —78 °C to yield a single geometrical isomer (eq 3).  

The lower-order silyl cuprates are apparently less reactive than the higher-order cuprates in conjugate addition reactions. Reagent (1) has been added in an addition-elimination sequence to an alkylidenemalonate system as a route to vinylsilanes (eq 4).  

This reaction was a prelude to a more elaborate scheme for producing more substituted vinylsilanes. The product of eq 4 further reacted with a geminal diorganometallic species to yield an ( )/(Z) (86 14) mixture of a vinylsilane (eq 5). 

Handling, Storage, and Precautions thermally stable up to ambient temperatures oxygen- and moisture-sensitive use in a fume hood. 

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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. Lithium Cyano(dimethylphenylsilyl)-cuprate Trimethylsilyllithium. 

DilithiumCyanobis(dimethylphenylsilyl)-cuprate Dimethylphenylsilyllithium Lithium Bis[dimethyl(phenyl)silyl]cuprate Lithium Cyano(dimethylphenylsilyl)cuprate E) 1-Trimethylsilyl-1,3-butadiene... 

PDMS LiCuCN Lithium Cyano(dimethylphenylsilyl)cuprate 75583-56-1 353... 

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