ORGANIC NAMED REACTIONS
1. Aldol Condensation :
Aldehydes having α - hydrogen (s) undergo self-condensation on warming with dilute or mild base to give β- hydroxy aldehydes , called aldols .
Aldehydes having α - hydrogen (s) undergo self-condensation on warming with dilute or mild base to give β- hydroxy aldehydes , called aldols .
2. Benzillic Acid Rearrangement :
Benzil on treatment with a strong base forms benzillic acid (salt) , hence the name benzillic acid rearrangement .
Benzil on treatment with a strong base forms benzillic acid (salt) , hence the name benzillic acid rearrangement .
3. Birch Reduction :
When aromatic rings are reduced with sodium , potassium or lithium in liquid ammonia or amine in the presence of alcohol , addition of hydrogen
takes place
at position 1 and 4 to give an unconjugated diene. When aromatic rings are reduced with sodium , potassium or lithium in liquid ammonia or amine in the presence of alcohol , addition of hydrogen
takes place
4. Cannizzaro Reaction :
In presence of a strong base , aldehydes without alpha - hydrogen , i.e. nonaldolizable aldehydes undergo self oidation reduction , i.e., disproportion reaction .
In presence of a strong base , aldehydes without alpha - hydrogen , i.e. nonaldolizable aldehydes undergo self oidation reduction , i.e., disproportion reaction .
5. Claisen Rearrangement :
Claisen rearrangement involves the shift of a group from oxygen to carbon . Thus, when aryl allyl ethers are heated (2000C) they rearrange to o-allylphenols .
Claisen rearrangement involves the shift of a group from oxygen to carbon . Thus, when aryl allyl ethers are heated (2000C) they rearrange to o-allylphenols .
6. Clemmenson Reduction :
The reduction of carbonyl group of aldehydes and ketones to methylene groups with amalgamated zinc and conc. HCL .
The reduction of carbonyl group of aldehydes and ketones to methylene groups with amalgamated zinc and conc. HCL .
7. Diels - Alder Reaction :
Diels-Alder Reaction involves the 1,4-addition of an alkene to a conjugated diene to form an adduct of six-membered ring .
Electron-Withdrawing-Group (EWG) in the dienophile , such as >C=O , -CHO , -COOR , -CN , -NO2 , etc . promotes the reaction .
The reaction is also accelerated by the presence of electron-releasing groups in the dienes .
Diels-Alder Reaction involves the 1,4-addition of an alkene to a conjugated diene to form an adduct of six-membered ring .
Electron-Withdrawing-Group (EWG) in the dienophile , such as >C=O , -CHO , -COOR , -CN , -NO2 , etc . promotes the reaction .
The reaction is also accelerated by the presence of electron-releasing groups in the dienes .
8. Fridel-Craft Reaction :
Alkylation and acylation of the aromatic compounds with alkyl halides and acid halides or anhydrates in the presence of a metal halide (Lewis acid)
is known as Fridel-Craft Reaction .
The order of Reactivity of some catalysts is : AlBr3 > AlCl3 > FeCl3 > SbCl5 > SnCl4 > BCl3 > BF3
Alkylation and acylation of the aromatic compounds with alkyl halides and acid halides or anhydrates in the presence of a metal halide (Lewis acid)
is known as Fridel-Craft Reaction .
The order of Reactivity of some catalysts is : AlBr3 > AlCl3 > FeCl3 > SbCl5 > SnCl4 > BCl3 > BF3
9. Fries Rearragnement :
Phenolic esters on heating with aluminium trichloride (Lewis acid) gives o- and p- aryl phenol .
In general , low temp. favours the para-product and high temp. favours ortho-product .
Phenolic esters on heating with aluminium trichloride (Lewis acid) gives o- and p- aryl phenol .
In general , low temp. favours the para-product and high temp. favours ortho-product .
10. Gabriel Syntheis :
The reaction involves the preparation of primary amines free from secondary or tertiary amines by reacting alkyl halides with alkali
phthalimide and subsequent hydrolysis .
The reaction involves the preparation of primary amines free from secondary or tertiary amines by reacting alkyl halides with alkali
phthalimide and subsequent hydrolysis .
11. Hell-Volhard-Zelinsky Reaction :
Aliphatic carboxylic acids reacts with bromine or chlorine (but not iodine and flourine) in the presence of small amount of red phosporous
to give exclusively mono alpha-halogenated acids . [Only by aliphatic acids having alpha-hydrogen ] .
Aliphatic carboxylic acids reacts with bromine or chlorine (but not iodine and flourine) in the presence of small amount of red phosporous
to give exclusively mono alpha-halogenated acids . [Only by aliphatic acids having alpha-hydrogen ] .
12. Hoffmann Rearrangment :
The reaction involves the conversion of an amide into a primary amine with one carbon loss , by the action of alkaline hypohlaite (NaOH solution + Br2 or Cl2)
The reaction involves the conversion of an amide into a primary amine with one carbon loss , by the action of alkaline hypohlaite (NaOH solution + Br2 or Cl2)
13. Knoevenagel Reaction :
Condensation of aldehydes and ketones with compounds having active methylene group in the presence of basic catalyst to form alpha,beta - unsaturated compounds .
Condensation of aldehydes and ketones with compounds having active methylene group in the presence of basic catalyst to form alpha,beta - unsaturated compounds .
14. Michael Reaction :
The base-catalysed addition of compounds having active methylene group (or relatively acidic hydrogen) to an activated olefinic bond of the type
>C=C-Z (Z = EWG) is classified as Michael Reaction .
The base-catalysed addition of compounds having active methylene group (or relatively acidic hydrogen) to an activated olefinic bond of the type
>C=C-Z (Z = EWG) is classified as Michael Reaction .
15. Oppenauer Reaction :
The oxidation of a secondary alcohol with a ketone and a base to the corresponding ketone of the alcohol .
The oxidation of a secondary alcohol with a ketone and a base to the corresponding ketone of the alcohol .
16. Perkin Reaction :
In Perkin reaction , condensation has been effected between aromatic aldehydes and aliphatic acid anhydrides in the presence of sodium or potassium salt of the acid corresponding
to the anhydride , to yield alpha,beta - unsaturated aromatic acids . The acid reaction should have at least two alpha-hydrogens .
In Perkin reaction , condensation has been effected between aromatic aldehydes and aliphatic acid anhydrides in the presence of sodium or potassium salt of the acid corresponding
to the anhydride , to yield alpha,beta - unsaturated aromatic acids . The acid reaction should have at least two alpha-hydrogens .
17. Pinacol - Pinacalone Rearrangment :
The acid catalysed rearrangemnt of diols (1,2-diols) to ketones or aldehydes with elimination of water is known as pinacal or pinacol-pinacalone rearrangment .
The acid catalysed rearrangemnt of diols (1,2-diols) to ketones or aldehydes with elimination of water is known as pinacal or pinacol-pinacalone rearrangment .
18. Reformasky Reaction :
Reaction of alpha-halo ester , usually an alpha-bromoester with an aldehyde or ketone in the presence of zinc metal to produce a beta-hydroyester .
Reaction of alpha-halo ester , usually an alpha-bromoester with an aldehyde or ketone in the presence of zinc metal to produce a beta-hydroyester .
19. Reimer Tiemann Reaction :
Formylation of phenols with chloroform in alkaline solution .
Formylation of phenols with chloroform in alkaline solution .
20. Schmidt Reaction :
Carboxylic acid and hydrzzoic acid react in the presence of sulphuric acid to give amines .
Carboxylic acid and hydrzzoic acid react in the presence of sulphuric acid to give amines .
21. Ullmann Reaction :
The sysntesis of diphenyl amines , diphenyl amines , diphenyl ethers and diphenyls is known as Ullmann Reaction .
The sysntesis of diphenyl amines , diphenyl amines , diphenyl ethers and diphenyls is known as Ullmann Reaction .
22. Wittig Reaction :
Synthesis of alkenes by the treatment of aldehydes or ketones with alkylidenetriphenylphosphorane (Ph3 = CR2) or simply known as phosphorane
23.Wolff-Kishner Reaction :Synthesis of alkenes by the treatment of aldehydes or ketones with alkylidenetriphenylphosphorane (Ph3 = CR2) or simply known as phosphorane
Involves the conversion of carbonyl groups of aldehydes and ketones to methylene groups by heating their hydrozones , semicarbazones or azines in the presence of strong base such as NaOH or C2H5ONa .
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