3-Pentanone cyanohydrin

Ethyl tert-butvl ether. Ethylene dibromide, Ethyl ether, Ethvl sulfide. 2-Heptanone, Methanol, 2-Methyl-1,3-butadiene, 2-Methvl-2-butene. Methyl chloride, Methylene chloride, Methyl iodide. Methyl mercaptan, 2-Methylphenol, Methyl sulfide. Monuron. Nitromethane, 2-Nitropropane, A-Nitrosodimethylamine, 1-Octene, 2-Pentanone, Propylene oxide, Styrene, Thiram, Toluene, Vinyl chloride, o-Xylene, tn-Xylene Formaldehyde cyanohydrin, see Acetontrile,... 

Exercise 16-12 Explain what factors would operate to make the equilibrium constant for cyanohydrin formation 1000 times greater for cyclohexanone than for cyclo-pentanone. Why What would you expect for cyclobutanone relative to cyclopenta-none Why ... 

The overall two-step process is illustrated with benzaldehyde and involves the reaction of the aldehyde with NaCN to give 30, followed by hydrolysis (the term for the acid-base reaction with aqueous acid) to give 33 (known as a cyanohydrin). Similarly, 2-pentanone leads to 31 and hydrolysis gives 34 buta-nal reacts with methylmagnesium bromide to give 32, and hydrolysis gives alcohol 35. 

The protection of carbonyl functions by reaction with trimethylsilyl cyanide to form the cyanohydrin trimethylsilyl ethers is subject to catalysis by potassium cyanide in the presence of 18-crown-6, tetrabutylammonium cyanide or resin bound tetraalkyl-ammonium cyanide [27, 29]. The nucleophilic cyanide ion is believed to attack the carbonyl yielding a cyanohydrin anion. This anion is silylated by trimethylsilyl cyanide with generation of an equivalent of cyanide anion. The sequence is shown in equation 7.13. Accordingly, 3-pentanone and 4- -butylcyclohexanone are cyanosil-... 

Other cyanohydrins can also be used in the transcyanation prcKjedure, provided that the corresponding carbonyl compound is not a good substrate for the enzyme. The successful application of the racemic cyanohydrins of 2-pentanone and 2-hexanone has been described [102,111] (see G.1.6). 

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