4-Cyclohexyl-4-methyl-2-pentanone

Probkm 28.28 Using 9-BBN plus any alkenes and unhalogenated acids or ketones, outline all steps in the synthesis of (a) 2-heptanone (b) 4-methylpentanoic acid (c) 4-methyl-2-hexanone (d) l-cyclohexyl-2-propanone (e) ethyl (trans Z-methylcyclopentyl)acetate (f) l>phenyl-4-methyM-pentanone (g) i-cyclopentyl-33 dimethyl-2-butaBone. 

The final unequivocal experimental proof that the observed effects were indeed peripheral ones was obtained in psychophysical experiments. Tertiary butyl mercaptan was used as the target in a monorhinal presentation. Its perceived odor intensity remained unchanged when in a dichorhinal experiment the contralateral na-ris was exposed to a very low Intensity of l -cyclohexyl-l -methyl-2-pentanone (CMP, 13). However, in agreement with established crossover additivity, the total perceived overall odor intensity showed a small, but statistically significant increase. Then the two separate odorant streams of the dichorhinal experiment were combined and the mixture of malodor (t.-butyl mercaptan) and AMAL (CMP) presented to the subjects again. Perceived overall intensity was reduced by and perceived malodor intensity by 85 at a significance level of 5%. 

Predict the position of acid-catalyzed bromination of each of the following ketones (a) 2-butanone, (b) 2-pentanone, (c) 3-methyl-2-butanone, (d) 2-methylcyclohexanone, and (e) methyl cyclohexyl ketone. 

Give one reasonable disconnection for (a) 3-methyl-l-phenyl-l-pentanone and (b) 3-cyclohexyl-2-methyl-3-hexanol. 

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