Aldol condensation

Aldol condensation

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  ALDOL CONDENSATION PRESENTED BY:MR K V NANDA KUMAR ASSOCIATE PROFESSOR KRISHNA TEJA PHARMACY COLLEGE, TIRUPATHI-517506 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 1
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  Aldol Condensation The aldolcondensation reaction is an organic reaction introduced by Charles Wurtz, who first prepared the β-hydroxy aldehyde from acetaldehdye in 1872. Two molecules of an aldehyde or a ketone undergo a condensation reaction in the presence of a base to yield β – hydroxyaldehyde or β – hydroxyketone. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 2
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  Aldols An aldol oraldol adduct (from "aldehyde alcohol") is a hydroxy ketone or aldehyde, and is the product of aldol addition (as opposed to aldol condensation, which produces an α,β-unsaturated carbonyl moiety). When used alone, the term "aldol" may also refer specifically to the compound 3-hydroxybutanal 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 3
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  General Aldol CondensationReaction 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 4  Aldol Condensation can be defined as an organic reaction in which enolate ion reacts with a carbonyl compound to form β-hydroxy ketone or β-hydroxy aldehyde, followed by dehydration to give a conjugated enone.  Aldol Condensation plays a vital role in organic synthesis, creating a path to form carbon-carbon bonds.
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  Mechanism of aldolcondensation Step 1: In reverse order, the hydroxide ion deprotonates the aldehyde. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 5 Aldehyde Enolate ionHydroxide ion Water
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  Mechanism of aldolcondensation Step 2: Here Enolate ion 1 adds to the unreacted aldehyde. . 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 6 Unreacted Aldehyde Enolate ion Alkoxide ion
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  Mechanism of aldolcondensation Step 3: Alkoxide ion 2 is protonated by water. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 7 Alkoxide ion Water Aldol Hydroxide ion
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  Mechanism of aldolcondensation Step 4: A small amount of aldol is converted into enolate ion (4) by hydroxide ion. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 8 Aldol Hydroxide ion Enolate ion Water
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  Mechanism of aldolcondensation Step 5: Here Enolate Ion(4) loses a hydroxide ion. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 9 Step 1 to step 3 illustrates the aldol reaction.
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  Crossed aldol condensation Thecondensation reaction between two different molecules of an aldehyde or ketone in a protic solvent such as water or alcohol constitutes the crossed aldol reaction. When condensation is between two different carbonyl compounds, it is called crossed aldol condensation. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 10
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  Questions 1. What isaldol condensation? 2. Give one example for aldol condensation reaction. 3. Explain the mechanism of aldol condensation. 12-06-2020 PHARM D YEAR I POC-MR K V NANDA KUMAR 11
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