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Clemmensen Reduction The Clemmensen Reduction allows the deoxygenation of aldehydes or ketones, to produce the corresponding hydrocarbon. The substrate must be stable to strong acid. The Clemmensen Reduction is complementary to the  Wolff-Kishner Reduction , which is run under strongly basic conditions. Acid-labile molecules should be reduced by the Wolff-Kishner protocol. Mechanism of the Clemmensen Reduction The reduction takes place at the surface of the zinc catalyst. In this reaction, alcohols are not postulated as intermediates, because subjection of the corresponding alcohols to these same reaction conditions does not lead to alkanes. The following proposal employs the intermediacy of zinc carbenoids to rationalize the mechanism of the Clemmensen Reduction:

CHEMISTRY XII SET -1

ORGANIC – CHEMISTRY (SAMPLE QUESTION) SET-1                                                                                                    MM  -30 Q1-Explain of the following- (2x3) a-Why only phenol show acidic nature but other alcohol not? b-Why aniline have more Pka value then methyl amine? c-Why aniline does not give friedal craft reaction? Q2-write short notes on the following reaction—(2x4) a-Garbriel pthalamide reaction. b -Halloform recation. c-carbylamine reaction. d-Reimer tiemann reaction. Q3- How you will convert the following- (2x3) a-Phenol into asprin. b-Acetaldehyde into 3-hydroxybutanoic acid. c-Propanamine into ethanamine. Q4-How you wil differenciate between the following- (2x3) a-Phenol and ethyl alcohol. b-Aniline and N-methyl aniline. c.Pentane 2- one and pentane 3- one. Q5 -Compound A having general formula C8 H 8O ,give Tollen test and undergoes cannizaro reaction.This compound B (C

name reaction-clemenson reaction

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Clemmensen Reduction The Clemmensen Reduction allows the deoxygenation of aldehydes or ketones, to produce the corresponding hydrocarbon. The substrate must be stable to strong acid. The Clemmensen Reduction is complementary to the  Wolff-Kishner Reduction , which is run under strongly basic conditions. Acid-labile molecules should be reduced by the Wolff-Kishner protocol. Mechanism of the Clemmensen Reduction The reduction takes place at the surface of the zinc catalyst. In this reaction, alcohols are not postulated as intermediates, because subjection of the corresponding alcohols to these same reaction conditions does not lead to alkanes. The following proposal employs the intermediacy of zinc carbenoids to rationalize the mechanism of the Clemmensen Reduction: