Reactions Elimination and Dehalogenation

Reactions. - Elimination and Dehalogenation. Mild conditions for eliminating primary alkyl halides to form 1-alkenes have been reported in which a solution of the halide and DBU in THF is added to a solution prepared by the reaction of an equivalent of dichlorobis(triphenylphosphinato)nickel and two equivalents each of triphenylphosphine and butyl-lithium.1 Polyethylene glycol promoted basic dehydrohalogenation of 1,1-dibromoalkenes has been 

Coupling Reactions. The palladium-catalysed cross-coupling of E—(1-alkyl-l-alkenyl)boronates with alkyl halides has been shown to permit stereo- and regio-specific access to trisubstituted alkenes in which the introduced alkyl group occupies the position formerly occupied by the boron substituent.201 A1lyl-silanes may be obtained 

Aryl or vinyl iodides and benzyl or allyl halides may be reductively formylated with carbon monoxide to give the 

The use of octacarbonyldicobalt and carbon monoxide in the presence of calcium hydroxide and methyl iodide has been found to furnish mixtures of the carboxylic acids and a-keto-carboxylic acids 

Terminal halide systems (26), (27), and (28) undergo free-radical 

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