Crotyl cyanide

Coumalic acid, 56, 51 Crotyl fluoride, 57,73 18-CROWN-6,57, 30 Curtius rearrangement, 59, 1 Cyanide ion, as catalyst for conjugate addition of aldehydes, 59, 56 p-Cyanobenzenesulfonyl cyanide, 57, 89 2-( 1 -Cyanocyclohexyljhydrazinecarboxylic acid methyl ester, 58,102 Cy a noferrocene, 56, 30 Cyanogen chloride, 57, 88... 

It was suggested that this change in product distribution was due to the existence of an equilibrium between two types of complex, viz., a cr-butenyl-pentacyanocobaltate(III) and a 7r-butenyltetracyanocobaltate(III) 107, 109). However, further study of the kinetics and product distribution suggested the presence of two o-bonded complexes, viz., cr-but-l-en-3-yl and a-but-2-en-l-yl 24a). Direct evidence for the existence of a cyanide-dependent equilibrium between the a- and rr-bonded organocyanide complexes has been obtained from NMR studies of the complex prepared by the reaction of allyl halides with Co—H 109) (see also Section V,C). Both butadiene and crotyl chloride react with Co—H to give the same... 

The formation of olefinic nitriles from allylic halides is best accomplished with dry, powdered cuprous cyanide rather than with alcoholic alkali cyanides, with which side reactions such as isomerization and alcoholysis of the double bond are particularly bothersome. With cuprous cyanide the yields in the synthesis of allyl cyanide and methal-lyl cyanide are 84% and 86%, respectively. Higher allylic halides are subject to allylic rearrangements thus cuprous cyanide acts on crotyl halide (CH,CH CHCHjX) and methylvinylcarbinyl halide (CH,CHXCH = CH,) to produce the same mixture of isomeric nitriles (9 1) regardless of which halide is treated. Numerous cyanides of the allylic type (Cj-Ci4) have been prepared, although the possibility of an isomerization has not been considered. A similar isomerization has been observed in the reaction of sorbyl chloride and potassium cyanide. ... 

Condensation of 1 with 3,4-dimethoxybenzyl cyanide afforded the epimeric cyano alcohols 2, which on alkaline hydrolysis gave the epimeric y -lactones 3 in 64% yield. Treatment of 3 with crotyl bromide afforded the a,a-disubstituted lactone 4. Acid-catalyzed debenzy-lation of 4 afforded the alcohol 5, which on sequential saponification, periodate cleavage and reduction gave the lactone 7 via 6. Palladium-catalyzed oxidation of 7 afforded 8, which underwent intramolecular cyclization to produce 9 in 66% yield. Treatment of 9 with methylamine gave 10 (41%) and 11 (7%) however, the former can be cyclized into the latter in 85% yield. Reduction of 11 furnished 12 in 77% yield. 

Nucleophile = Allyl/crotyl silanes, Allyl/crotyl stannanes, Silyl enol ethers, Silyl ketene acetals, Silyl hydrides. Metal cyanides. Alkyl zincs... 

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