How Are Derivatives of Carboxylic Acids Reduced

Show how to prepare each alcohol by treating an ester with a Grignard reagent  

Most reductions of carbonyl compounds, including aldehydes and ketones, are now accomplished hy transferring hydride ions from horon or aluminum hydrides. We have already seen the use of sodium horohydride to reduce the carhonyl groups of aldehydes and ketones to hydroxyl groups (Section 12.10B). We have also seen the use of lithium aluminum hydride to reduce not only the carhonyl groups of aldehydes and ketones, hut also carhoxyl groups (Section 13.5A), to hydroxyl groups. 

An ester is reduced by lithium aluminum hydride to two alcohols. The alcohol derived 

Sodium horohydride is not normally used to reduce esters because the reaction is very slow. Because of this lower reactivity of sodium horohydride toward esters, it is possible to reduce the carbonyl group of an aldehyde or a ketone to a hydroxyl group with this reagent without reducing an ester or a carboxyl group in the same molecule  

Reduction of amides by lithium aluminum hydride can be used to prepare 1°, 2°, or 3° amines, depending on the degree of substitution of the amide  

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How Are Derivatives of Carboxylic Acids Reduced 14E Systematic Acquired Resistance in Plants... 

In the last 20 years, the variety of ligands available for rhodium and ruthenium-catalysed hydrogenations has increased to the point where the right combination of metal and ligand will reduce almost any unsaturated carboxylic acid derivative in high enantiomeric excess. Details are beyond the scope of this book, but we leave you with four examples, all from industrial drug syntheses, to illustrate how versatile the method can be. 

In the discussion of translation, the amino acids were taken for granted. In this chapter we must discuss several aspects of their biosynthesis. Their name is derived from the fact that in all frequently occurring amino acids an amino group is found in the a-position to a carboxyl group. We shall concern ourselves first with the origin of this reduced N and then see how it is transferred to the C skeleton, i.e. how the amino acids are formed. 

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