Chapter 23, Problem 12P

Interpretation Introduction

Interpretation:

A synthetic strategy of converting stearic acid to given products is to be devised.

Concept Introduction:

Electrophiles are electron deficient species which has positive or partially positive charge. Lewis acids are electrophiles which accept electron pair.

Nucleophiles are electron rich species which has negative or partially negative charge. Lewis bases are nucleophiles which donate electron pair.

Free radical is an atom, molecule or ion that has unpaired electrons which makes it highly chemically reactive.

Substitution reaction: A reaction in which one of the hydrogen atoms of a hydrocarbon or a functional group is substituted by any other functional group is called substitution reaction.

Elimination reaction: A reaction in which two substituent groups are detached and a double bond is formed is called elimination reaction.

Addition reaction: It is the reaction in which unsaturated bonds are converted to saturated molecules by the addition of molecules.

Carboxylic acids can be converted to acid chlorides using thionyl chlorides. Acid chlorides can be converted to ketones using Gilman reagent.

Amides can be reduced to amine using lithium aluminum hydride $\left({\text{LiAlH}}_{\text{4}}\right)$. Amides can be reduced to amines with one less carbon using Hofmann rearrangement. Carboxylic acids can be reduced to alcohols using either lithium aluminum hydride (LiAlH₄) or borane.

Alcohols can be converted to alkyl bromides using phosphorous tribromide (PBr₃).

Carboxylic acids can be converted to esters using either Fischer esterification or Steglich esterification. In Fischer esterification, alcohols and carboxylic acids are condensed using catalytic amounts of concentrated sulfuric acid.

Steglich esterification, on the other hand, employs DCC (N,N´-dicyclohexylcarbodiimide) in conjunction with DMAP (4-dimethylaminopyridine) catalyst.

Carboxylic acids can be coupled with secondary amines using coupling agent like $\text{2-chloro}-4,6-\text{dimethoxy}-1,3,5-\text{triazine}$(CDMT) in conjunction with N-methylmorpholine (NMM) to form amides.

Stearic acid can be first converted to stearoyl chloride, which can subsequently be converted to ethyl stearate using ethyl alcohol.

The stearic acid is converted to ethyl stearate in the presence of tert-butyl alcohol, DCC and DMAP.

Stearic acid can first be converted to stearoyl chloride, which can then be allowed to react with ammonia to form stearamide.

The stearic acid can be coupled with dimethylamine using $\text{2-chloro}-4,6-\text{dimethoxy}-1,3,5-\text{triazine}$(CDMT) in conjunction with N-methylmorpholine (NMM) to form N,N-dimethylstearamide.

The stearic acid is converted to stearamide, and then the stearamide is reduced with LiAlH₄ to form octadecyl amine.

The stearic acid can first be converted to stearamide, which can then be converted to heptadecylamine using Hofmann rearrangement.

Octadecanal can be prepared by first reducing stearic acid to 1-octadecanol, and then oxidizing 1-octadecanol with Dess–Martin periodinane.

Octedecyl stearate can be prepared from the condensation of stearic acid and octadecyl alcohol using Fischer esterification.

Stearic acid can be converted to 1-octadecanol by borane reduction.

2-Nonadecanone can be made first by converting stearic acid to stearoyl chloride.

1-Bromooctadecane can be prepared by first converting stearic acid to 1-octadecanol and then reaction of 1-octadecanol with ${\text{ PBr}}_3$.