| Abstract
| - Allylic carbonates are cyanated in high yields to β,γ-unsaturated carbonitriles usingtrimethylsilyl cyanide in the presence of a catalytic amount (5 mol %) of Pd(PPh3)4 in THFunder reflux. In the reaction, cinnnamyl methyl carbonate affords cinnamyl cyanide in 98%yield. Allylic acetates also provide the corresponding carbonitriles, but often in lower yields.The cyanations of several cis- and trans-alicyclic substrates proceed cleanly (stereoselectivity> 99%) with overall retention. Characterization and reaction of palladium complexesrelevant to the present catalysis indicate that transmetalation of an η3-allyl palladiumcomplex with trimethylsilyl cyanide is facile, while the resulting cyano(η3-allyl)palladiumcomplexes afford the corresponding allylic cyanides only when excess trimethylsilyl cyanideis present. Stereochemistry of the product indicates that the CN attacks the η3-allyl moietiesfrom the palladium side.
- Allylic carbonates (2) are cyanated in high yields to β,γ-unsaturated carbonitriles (3) using trimethylsilyl cyanide in the presence of a catalytic amount (5 mol %) of Pd(PPh3)4 in THF under reflux, while allylic acetates (1) often afforded the products in lower yields. The cyanations of several cis- and trans-alicyclic substrates proceed cleanly (stereoselectivity > 99%) with overall retention.
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