Summary of Ketone Chemistry

Problem 15.49 By rapid test-tube reactions distinguish between (a) pentanal and diethyl ketone, (h) diethyl ketone and methyl n-propyl ketone, (c) pentanal and 2,2-dimethylpropanal, d) 2-pentanol and 2-pentanone. 

Problem 15.50 Show steps in the following syntheses (a) acetyl chloride to acetal (CH,CH(OC,H,)j), (b) allyl chloride to acrolein (propenal), (c) ethanol to 2-butene.  

Problem 15.51 Use benzene and any aliphatic and inorganic compounds to prepare (a) 1,1-diphenylethanol, (( ) 4,4-diphenyl-3-hexanone. 4 

Since it is easier to make C H,COCH, than (C H,),CO from C H, the latter pair is used. Benzene is used to prepare both intermediate products. 

Problem 15.52 Use butyl alcohols and any inorganic materials to prepare 2-methyl-4-heptanone. The indicated bond 

Problem 15.36 (a) What properties identify a carbonyl group of aldehydes and ketones (b) How can aldehydes and ketones be distinguished  

Problem 15.37 What are the similarities and differences between C=0 and C=C bonds 4 

Both undergo addition reactions. They differ in that the C of C=0 is more electrophilic than a C of C=C, because O is more electronegative than C. Consequently, the C of C=0 reacts with nucleophiles. The C=C is nucleophilic and adds mainly electrophiles. 

Problem 15.38 Give another acceptable name for each of the following (a) dimethyl ketone, (b) 1-phenyl-2 -butanone, (c) ethyl isopropyl ketone, (d) dibenzyl ketone, (e) vinyl ethyl ketone. -4 

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In summary, ketoreductases have emerged as valuable catalysts for asymmetric ketone reductions and are preparing to enter the mainstream of synthetic chemistry of chiral alcohols. These biocatalysts are used in three forms wild-type whole-cell microorganism, recombinant... 

For several tautomeric systems ketones/enols, imines/enamin and others) a distinct reversal of the stability order is observed when going from the neutral compounds to the radical cations, the first use of which in a new preparative a-Umpolung reaction has been documented for keto/enol systems. The present review provides a critical evaluation of the chemistry of enol radical cations in solution with a special emphasis on the Umpolung reaction and the intermediates thereof. Other enol type of radical cations are discussed with respect to their potential to provide a-carbonyl radical and a-carbonyl cation intermediates. Hence, this article does not constitute a comprehensive summary on all enol type of radical cation reactions. All potentials in this review are referenced versus SCE, unless noted otherwise. Potentials measured against the ferrocene/ferrocenium couple were converted to SCE by adding 0.334 V. 

Kekule, 189 Ketals, 293, 317 Ketones, oxidation of, 311 summary of chemistry, 325 Knoevenagel reaction, 393 Kodel, 371 Kolbe synthesis, 438... 

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