Nitriles alkenes

Conjugate reductions and Michael alkylations of alkene nitriles are found in Section 74D (Alkyls from Alkenes). 

The chemoselectivity of Schwartz s reagent (1) toward alkynes, alkenes, nitriles, and carbonyl groups, and thus its general functional group compatibility, can be modulated. However, it is important to keep in mind that the presence of functional groups may have regiochemical consequences on the hydrozirconation reaction. 

In the course of investigation into new C-C bond formation processes, Hiyama has developed an efficient nickel-catalyzed arylcyanation of alkynes.67 The addition reaction of an aryl-CN bond to alkyne affords aryl-substituted alkene nitrile in good yield. Good regioselectivity is reported in the case of unsymmetrical alkynes with two sterically different substituents. 

Alkynes are usually alkylated under strongly basic conditions. Gregory Fu of MIT recently reported (J. Am. Chem. Soc. 125 13642, 2003) a much milder Pd and Cu mediated coupling, illustrated by the reaction of the terminal alkyne 7 with the alkyl iodide 8 to give 9. Alkyl bromides work equally well. It is exciting that ketones, esters, alkyl chlorides, alkenes, nitriles and acetals are compatible with the procedure. The key to the reaction is the use of the supporting carbene ligand 10. 

The trimethylsilyl group can rigorously control and direct the Beckmann fragmentation leading to the regio- and stereo-specific formation of unsaturated nitriles (equations 41 to 43). Oxime acetate (57) fragments to the cij-alkenic nitrile (58) in 90% yield, whereas its epimer (59) affords the franj-alkenic nitrile (60) in 94% yield under the same conditions. Furthermore, fluoride-induced fragmentation can re-... 

The deactivation of B-MFI catalyst was not attributed to carbon deposition but to pore-blocking caused by an enrichment of nitrogen-containing species inside the pore system [27]. It was assumed that these species were formed by oligomerization or polymerization of alkene nitriles. If this is so the reaction before deae-tivation occurs mainly inside the pores of the MFI zeolite. 

The investigated supported complexes 22 and 23, outlined in Fig. 8, were used for hydrogenations of alkenes, nitriles and a,jS-unsaturated ketones. Furthermore, 23 was used in the reduction of different heterocycles like benzoth-iophene, quinoline, indole, dibenzothiophene and acridine. The supported chiral Rh complexes, depicted in Fig. 9, were used for hydrogenation reactions with prochiral olefins. 

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