Ketones, from alkyls

This reaction sequence is called the acetoacetic ester synthesis. It is a standard procedure for the preparation of ketones from alkyl halides, as the conversion of 1-bromobutane to 2-heptanone illustrates. 

SECTION 170 KETONES FROM ALKYLS, METHYLENES AND ARYLS... 

This section lists examples of the replacement of hydrogen by ketonic groups, R-H R(C=0)-R . For the oxidation of methylenes, R2CH2 -> R2C=0, see section 170 (Ketones from Alkyls). 

For the oxidation of allylic methylene groups (C=C-CH2 C=C-C=0), see Section 170 (Ketones from Alkyls and Methylenes). 

Radical carbonylation reaction serves as a powerful tool for the synthesis of a range of carbonyl compounds. Radical carbonylation has been successfully applied to the synthesis of functionalized ketones from alkyl, aryl, and alkenyl halides.The radical aminocarbonylation reaction of alkynes and azaenynes provided efficient routes to 2-substituted acrylamides, lactams, and pyrrolidinones. For example, the aminocarbonylation of 4-pentyn-l-yl acetate 318 initiated by tributyltin hydride (Bu"3SnH) (30mol%) with AIBN (20mol%) gave acrylamide 325 in 92% yield (Scheme 43).A proposed mechanism starts from the addition of tributyltin radical 319 to alkyne... 

Formylation and acetylation of a primary alkyl bromide.2 Detailed directions are available for preparation of disodium tctracarbonylferratesesquidioxanate, Na2Fe(CO)4(dioxanc), 5 (1), and for use of the reagent for preparation of aldehydes and ketones from alkyl bromides. 

Oxidation of Other Arenes. Aromatic compounds with longer alkyl side chains can be converted to ketones or carboxylic acids. All the previously discussed reagents except Cr02Cl2 usually afford the selective formation of ketones from alkyl-substituted arenes. Oxidation with Cr02Cl2 usually gives a mixture of products. These include compounds oxidized in the P position presumably formed via an alkene intermediate or as a result of the rearrangement of an intermediate epoxide.110,705... 

SECTION 170 Ketones from Alkyls, Methylenes, and Aryls... 

Dipotassium Iron tetracartxsnyl in the synthesis of aldehydes and ketones from alkyl halides. 

Katritzky and his co-workers have extended their investigations of the use of heterocycles in organic synthesis to give a synthesis of aldehydes and ketones from alkyl halides (Scheme 4). The same reagents can be used to effect the oxidation of primary amines to aldehydes, again in high yield (Scheme 5). ... 

Hashemi et al. (2004) synthesized aromatic aldehydes and ketones from alkyl halides without solvent using wet montmorillonite KIO supported iodic acid as oxidant. 

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