REACTIONS IN ORGANIC CHEMISTRY

Acids and bases catalyze the isomerization of N-glycosides (glycosamines) from aldoses to 1-aminodeoxyketoses. This rearrangement can be catalyzed with a number of Lewis acids (CuCl 2 , MgCl 2 , AlCl 3 , SnCl 4 ). The amine used as a reagent can be primary or secondary, aliphatic or aromatic.

amadori reaction 01

Acetylacetic synthesis allows ketones to be prepared by C-alkylation of ethyl acetylacetate (ethyl 3-oxobutanoate). Ethyl acetoacetate can be deprotonated at the C2 or C4 positions depending on the type and amounts of base used. The hydrogens at the C2 position they present significant acidity (pKa=11) due to stabilization of the conjugate base on the two neighboring carbonyls.In the presence of a base equivalent (alkoxides, LDA, NaHMDS, etc.) a ketoester enolate capable of attacking numerous carbonated electrophiles.

acetylacetic synthesis 01

Aldehydes and ketones [1] react with a,b -unsaturated compounds [2] in the presence of tertiary amines that act as catalysts, to form a -hydroxyalkylated products [3] .

 
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The Barton reaction produces 4-nitrosoalcohols [2] from nitrites [1] by irradiation with ultraviolet light.

 
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The tosylhydrazones of aldehydes or ketones react with two equivalents of organolico to generate an anionic intermediate capable of undergoing alkylation processes.

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The Baeyer Villiger oxidation allows the transformation of ketones into esters.

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The Claisen condensation involves the reaction of esters in basic medium forming 3-ketoesters

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acetyl chloride it is treated with diazomethane yielding the diazonium salt . chloride produced reacts with the diazonium salt to give the α-chloroketone .

Tosylhydrazones of aliphatic aldehydes or ketones react with strong bases to give alkenes .

Reacción de Bamford Stevens

In this reaction two alkenes and are treated with a transition metal that acts as a catalyst, giving a mixture of alkenes (including Z/E isomers). This product is obtained by exchange of alkylidene groups.

Aldol condensation is a reaction of aldehydes or ketones. which forms 3-hydroxycarbonyls (aldols) . 3-hydroxyaldehyde under dehydration conditions by heating yields an alpha, beta-unsaturated aldehyde .
Condensación aldólica

Acyloinic condensation transforms esters into alpha-hydroxyketones. This reaction is carried out with sodium metal in an inert solvent.

Condensación aciloínica

The Abuzov reaction is used in the synthesis of phosphonates from phosphites . The phosphonates obtained in the Abuzov synthesis are used as starting materials in the Horner-Wittig synthesis.

Reacción de Arbuzov