1- CYCLOHEXENYL ACETONITRILE

Nach Versuchen von Ingold, de Salas und Wilson (108) ist die Isomerisierung von Cyclohexenyl-acetonitril ein bimolekularer ProzeB. 

Potassium or lithium derivatives of ethyl acetate, dimethyl acetamide, acetonitrile, acetophenone, pinacolone and (trimethylsilyl)acetylene are known to undergo conjugate addition to 3-(t-butyldimethylsiloxy)-1 -cyclohexenyl t-butyl sulfone 328. The resulting a-sulfonyl carbanions 329 can be trapped stereospecifically by electrophiles such as water and methyl iodide417. When the nucleophile was an sp3-hybridized primary anion (Nu = CH2Y), the resulting product was mainly 330, while in the reaction with (trimethylsilyl)acetylide anion the main product was 331. 

Oxidation of cyclohexene by peroxydisulfate in the presence of copper(II) salts results in the formation of cyclopentanecarboxaldehyde as the main product in an aqueous acetonitrile solution (equation 261), and 2-cyclohexenyl acetate in an acetic acid solution (equation 262).588,589 Reaction (261) has been interpreted as the formation of a radical cation (186) by oxidation of cyclohexene with S2Og, followed by hydrolysis of (186) to the /3-hydroxy alkyl radical (187), which is oxidized by copper(II) salts to the rearranged aldehydic product (188 equation 263).589... 

In the synthesis of racemic 3-phosphoshikimic acid derivatives a palladium-catalyzed rearrangement of a cyclohexenyl phosphate was used for the stereochemical control of the C-3 oxygen function29. This rearrangement is considerably slower than the analogous reactions of allylic acetates and requires a stoichiometric amount of bis(acetonitrile)palladium(II) chloride. 

Treatment of methyl 2-benzoyl-2-cyclopropyl-3-iodopropanoate with chromium(II) acetate in acetonitrile afforded a mixture of cyclohexenyl and cyclohexadienyl esters (Section 2.4.1.5.9.). 

The products are colorless, air-stable Pt(II) cyclohexenyls. Nitromethane, acetonitrile or phenylacetonitrile react with Pt(CgHgXdppe) under anhydrous conditions, whereas methyl ketones react only in the presence of water via the preformed hydroxo complex. 

Isomerization of cis- and /ra/75-5-methyI-2-cyclohexenyl chlorides in acetonitrile solutions containing tetraethylammonium chloride was studied by Noyes and co-workers. These chlorides undergo simultaneous cis-trans isomerization, mutarotation, racemization and chloride exchange, e.g. 

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