Aldehydes, without alpha hydrogens, give the Cannizzaro reaction on treatment with a strong base (NaOH)


In this reaction one molecule is reduced to alcohol, while the other is oxidized to carboxylic acid.

The Blanc reaction allows the chloromethylation of aromatic compounds.

white reaction 01

It uses as reagents methane with gaseous hydrogen chloride in the presence of a Lewis acid. The result is the introduction of a hydroxymethyl group on the aromatic ring (benzene) whose hydroxyl is replaced by chlorine in the presence of hydrogen chloride.

The Beckmann reaction produces the rearrangement of an oxime into an amide. This reaction is carried out in an acid medium.

beckmann transposition 01

In 1989, G. Bartoli described the reaction of substituted nitroarenes with Grignard vinyl organometallics at low temperature, yielding substituted indoles after aqueous work-up. Three equivalents of magnesium are necessary, added to a cold nitroarene solution, which is stirred for twenty minutes, followed by the addition of saturated ammonium chloride solution and final extraction with ether. Better performance is obtained with indoles substituted in the ortho position to the nitro.
batoli indole synthesis 01

The Barbier reaction makes it possible to obtain unstable organometallic reagents in the reaction medium. Initially it was carried out with Magnesium metal, generating magnesium in situ. Later it was extended to other metals: Sn, Zn..., being able to work in aqueous media, without requiring the protection of acid groups (hydroxyls).

babier reaction 01

The Schiemann reaction consists of the thermal decomposition of aromatic diazonium tetrafluoroborates to yield the corresponding fluorinated derivative. Although diazonium salts are intestable, diazonium tetrafluoroborates have significant stability and can be prepared in good yield. Diazonium tetrafluoroborate is prepared from aromatic amines by the diazotization reaction.

Balz Shiemann 01

The Baker-Venkataraman rearrangement transforms aromatic ortho-acyloxyketones to beta-diketones by basic treatment (catalysis). Beta-diketones are of great interest in the synthesis of chromones, flavones and coumarins. The most commonly used bases in the reaction are: KOH, potassium tert-butoxide, sodium in toluene, potassium hydride.

baker venkataraman 01

1,5-Dienes isomerize by sigmatropic-[3,3] rearrangements on heating. Reaction known as Cope rearrangement. The rearrangement of N-substituted 1,5-dienes is called an aza-Cope rearrangement. Depending on the position occupied by nitrogen we have: 1-aza-, 2-aza-, 3-aza-Cope. The 3-aza-Cope regrouping coincides with the aza-Claisen.

aza cope 01

Sigmatropic [3,3] rearrangements of N-allyleneamines are known as aza-Claisen rearrangements. This reaction is analogous to the Claisen rearrangement of allyl vinyl ethers.

aza claisen 01

Reaction analogous to the Wittig rearrangement, in which alpha metal ethers rearrange alkoxides, generating secondary or tertiary alcohols after hydrolysis. In the case of aza-[2,3]-Wittig, these are alpha metallated allylic tertiary amines which produce secondary amines after hydrolysis.

aza23wittig 01

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] .


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


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


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


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

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.