1) Intuioduction & Mechanism of Mannich Reaction
> Defination
- compound containing atteast on active H² (Hyduiogen) atom condense with formaldehyde or Punimauiy (1°) or secondauiy (2°) amine or ammonia to give the product known as Mannich base
Reaction (Nucleophilic reaction)
Aeromatic ketone containing α-hydutoger undergoes Mannich reaction to fovm β-amino keton
Aceto ketone react with formaldehyde in Presence of Porimary / secondany amine to form β-amino ketone.
> Mechanism
- Neucleophile attack in N of NH² to amine electotopositive carbonyl carbon (c) of aldehyde to form inteumediate which is then protonated to form imine by oremoval of water.
Step - 1
Step - 2
- Reaction between enol from of aertomatic ketone & imine to from intermediate which is the diprotonated to from β-amino ketone.
2) Intuioduction & Mechanism of Oppanauer oxidation
Reaction
- oppanpueet oxidation is consider the reverse of Meerven-pondovif - verley reaction.
- Oppanaueut oxidation is gentle method or selectively oxcidiziqg 2°- alcohol to ketone.
oppanauey oxidation is an organic reaction Used to conveart a 1° or 2°-alcohol to ketone using another excess ketone reagent such as acetone. and aluminium catalyst.
Machanism
3) introduction & mechanism of meerven-pondorf-verley redution
Reaction
In thr method carbonyl compaund are reduce to the respective alcohol by the tretment with aluminium isopropaxide in isopropanol solution
The acetone so from is remove by slow distillation & hence the rection proceed in the desired direction.
Meeuiven - pondownf - Veutley Used aluminum ethoxide in then reduction.
The main advantages of the method lies in the mild condition high yield 60-90%
Howeveut aluminium isopropoxcide is the most widely used alcoxide as it effect rappid reaction with very few side reaction and superial yield as Compared with other alcoxides.
Aluminium being a very Strong lewis base reaction are geneuially carried out in IPA, Since acetone form is radify remove.
Machaism
Step 1
Step 2
Step 3
4) Introdution & Machanism Of Ullman Reaction
Reaction
It is also knowh as dimerization reaction
The preparation of di-aryl or poly-aryl compound by heating and aryl halide an anothrer amromatic compound with a little cu-powder or proper brone in nitro benzene solution is knowh as ullman reaction
Aryl chloride and bromide do not usually react unless their is an electro nagative group compound .
Mechanism
Probably ullman reaction process via a free redical mechanism
> Defination
- compound containing atteast on active H² (Hyduiogen) atom condense with formaldehyde or Punimauiy (1°) or secondauiy (2°) amine or ammonia to give the product known as Mannich base
Reaction (Nucleophilic reaction)
Aeromatic ketone containing α-hydutoger undergoes Mannich reaction to fovm β-amino keton
Aceto ketone react with formaldehyde in Presence of Porimary / secondany amine to form β-amino ketone.
> Mechanism
- Neucleophile attack in N of NH² to amine electotopositive carbonyl carbon (c) of aldehyde to form inteumediate which is then protonated to form imine by oremoval of water.
Step - 1
Step - 2
- Reaction between enol from of aertomatic ketone & imine to from intermediate which is the diprotonated to from β-amino ketone.
2) Intuioduction & Mechanism of Oppanauer oxidation
Reaction
- oppanpueet oxidation is consider the reverse of Meerven-pondovif - verley reaction.
- Oppanaueut oxidation is gentle method or selectively oxcidiziqg 2°- alcohol to ketone.
oppanauey oxidation is an organic reaction Used to conveart a 1° or 2°-alcohol to ketone using another excess ketone reagent such as acetone. and aluminium catalyst.
Machanism
3) introduction & mechanism of meerven-pondorf-verley redution
Reaction
In thr method carbonyl compaund are reduce to the respective alcohol by the tretment with aluminium isopropaxide in isopropanol solution
The acetone so from is remove by slow distillation & hence the rection proceed in the desired direction.
Meeuiven - pondownf - Veutley Used aluminum ethoxide in then reduction.
The main advantages of the method lies in the mild condition high yield 60-90%
Howeveut aluminium isopropoxcide is the most widely used alcoxide as it effect rappid reaction with very few side reaction and superial yield as Compared with other alcoxides.
Aluminium being a very Strong lewis base reaction are geneuially carried out in IPA, Since acetone form is radify remove.
Machaism
Step 1
Step 2
Step 3
Reaction
It is also knowh as dimerization reaction
The preparation of di-aryl or poly-aryl compound by heating and aryl halide an anothrer amromatic compound with a little cu-powder or proper brone in nitro benzene solution is knowh as ullman reaction
Aryl chloride and bromide do not usually react unless their is an electro nagative group compound .
Probably ullman reaction process via a free redical mechanism
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