Presented by Dhanashree Kavhale. M. Pharm.(Pharmaceutical Chemistry) 1st year.
Various organic named reactions are there in Advanced Organic Chemistry I, as some of them are explained along with their mechanism.
1. Ugi Reaction
2. Brook Rearrangement
3. Ullman Coupling Reactions
4. Dieckmann Reaction
5. Doebner-Miller Reaction
6. Sandmeyer Reaction
7. Michael Addition Reaction
3. Ugi Reaction
The Ugi reaction was first reported by I. Ugi in 1959.
it is classified as an isocyanide-based multicomponent
The reaction is usually conducted in a polar protic solvent
such as methanol, and some success in water has been
non-polar halogenated solvents prove detrimental, as
most amines are insoluble, favoring the occurrence of the
Ugi reaction is a multi-component reaction in organic
chemistry involving a ketone or aldehyde, an amine, an
isocyanide and a carboxylic acid to form a bis-amide.
4. A multicomponent reaction (MCR) is generally defined as any process
in which three or more reactants combine in one pot to form a
product that incorporates structural features of each reagent.
Mechanism of Ugi reaction :
1. Imine formation with amine v/s ketone.
2. Proton exchange ( forming iminium ion)
3. Nucleophilic addition of isocyanide.
4. Nucleophilic addition of carboxylic acid anion.
5. Numm’s Rearrangement.
5. Applications :
1. The Ugi reaction is one of the first reactions to be exploited explicitly
to develop chemical libraries. Eg: Isoquinolines from Ugi.
2. Additionally, many of the caine-type anesthetics are synthesized using
6. Sandmeyer Reaction
synthesis aryl halides from aryl diazonium salts using copper salts as
reagents or catalysts.
The Sandmeyer reaction is an example of a radical-nucleophilic
aromatic substitution (SRNAr).
Sandmeyer reaction is unique one as we can do transformation of
benzene such as halogenation, trifluoromethylation, hydroxylation
7. Mechanism of Sandmeyer's reaction :
1.Formation of nitrosonium ion:
2. Formation of benzodiazonium ion:
3. Single electron transfer and formation of aryl halide :
8. Application of Sandmeyer's Reaction:
1. Used for synthesis of aryl halides.
2. For Cynation eg: synthesis of fluanxol and Neoamphimedine.
3. Trifluoromethylation : Sandmeyer-type reactions can be used to
generate aryl compounds functionalized by trifluoromethyl
4. For hydroxylation process.
9. Brook Rearrangement
The rearrangement was first observed in the late 1950s by Canadian
chemist Adrian Gibbs Brook.
In organic chemistry the Brook rearrangement refers to any [1,n]
carbon to oxygen silyl migration.
It this reaction an organosilyl group switches position with the
hydrogen proton over a carbon to oxygen covalent bond under the
influence of base.
10. Mechanism of Brooks rearrangement:
Applications of Brook Rearrangement:
1. K.takede and co-workers synthesized the tricyclic core of cyanthins.
2. Developed an new synthetic strategy for the stereoselective
construction of 8 membered carbocyclic compound.
11. Ullman Coupling Reaction
The Ullmann reaction is an organic named reaction that involves the
coupling of two aryl halides in the presence of copper to yield a biaryl
as the product.
Traditionally this reaction is affected by copper, but palladium and
nickel are also effective catalysts.
General reaction is illustrated below:
12. mechanism of the Ullmann reaction:
formation of an active copper(I) species upon the introduction of the
aryl halide to an excess of metallic copper under relatively high
This copper(I) species undergoes further oxidative addition with
another haloarene molecule, linking the two molecules.
13. the copper compound formed by the two aryl halide molecules
undergoes reductive elimination, resulting in the formation of a new
carbon-carbon bond between the two aryl compounds.
1. Biphenylenes can be obtained from 2,2-diiodobiphenyl.
2. employed for the closure of five-membered rings.
3. Chiral reactants can be coupled into a chiral product via this reaction.
14. Doebner-Miller Reaction
This reaction is generally used for the synthesis of Quinolines with
substituents on the pyridinoid ring.
The Doebner–Miller reaction is the organic reaction of an aniline with
α,β-unsaturated carbonyl compounds to form quinolines.
his reaction is also known as the Skraup-Doebner-Von Miller quinoline
16. Dieckman Reaction
The Dieckman condensation is the intramolecular chemical reaction of
diesters with base to give β-keto esters.
named after the German chemist Walter Dieckman. The equivalent
intermolecular reaction is the Claisen condensation.
18. Applications of Dieckman reaction:
1. Dieckman condensation has been used to form five and six-membered
rings in a number of synthesis of natural products.
such as α-pinene, oestrone, cyclic indole, and so on.
19. Michael Addition Reaction
The Michael reaction is a nucleophilic addition reaction involving the
addition of a carbanion (or any other suitable nucleophile) to an 𝛼,𝛽-
unsaturated carbonyl compound that contains a functional group
which is electron-withdrawing in nature.
It belongs to the larger class of conjugate additions and is widely used
for the mild formation of carbon-carbon bonds.
Michael donor Michael acceptor
1. Michael addition to form a seven-membered oxazepane ring.
2. Used in preparation of di,tri, carboxylic acids.
3. Preparation of ketones and diketones.
4. Preparation of cyclopropane derivatives.
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