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ALIPHATIC PORTION
[1] Preparation of Aldehydes and Ketones
(a) From alcoholsPrimary alcohols in presence of oxidizing agents such as anhydrous CrO3 or PCC , or by
catalytic dehydrogenation with Cu at 573 K get oxidised to aldehydes whereas secondaryalcohols results in the formation of ketones.
R CH2 OHAnhydrous CrO 3 / PCC
OxidationR CHOR CHO
Cu / 573 K
Dehydrogenation1o AlcoholAldehyde Aldehyde
2 Cu O2 2 CuO+
R CH2 OH + CuO Cu OH2R CHO + +
Details of dehydrogenation
(b) From alkenesThe alkenes on treatment with ozone followed by reductive cleavage (by Zn dust and water)results in the formation of aldehydes whereas substituted alkenes form ketones.
CH CH2R O3+
O O
C C
OR
H
H
H
Zn / H2OH C
O
HR C
O
H +Alkene
Ozonide
Aldehydes
CH CH2R
R
O3+
O O
C C
OR
R
H
HZn / H2O
R C
O
R + H CO
H
Ketone Aldehyde
(c) From alkynesEthyne reacts with water in the presence of mercuric sulphate and sulphuric acid to yieldaldehyde i.e. ethanal. Other alkynes give ketones.
CH CH +HgSO 4H2SO4
H OHCH2 CH
O H
TautomerisationCH3 C
O
HEthyne Ethanalenol ( Unstable )
C CHR + H OH+ HgSO 4
H2SO4R C
O H
CH2
TautomerisationR C CH
3
O
Ketone
[2] Preparation of Aldehydes only
(a) From acid chlorides [ Rosenmund reduction ]
R C
O
ClH2
Pd - BaSO 4R C
O
H
Acid chloride Aldehyde
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(b) From Nitriles [ Stephen Reduction ]The reaction of alkanenitrile with HCl in the presence of anhydrous stannous chlorideyields corresponding imine, which on hydrolysis give corresponding aldehyde.
R C NSnCl 2
HClR CH NH
imine
OH3+
R CHO
(c) From Acid derivatives
AcidLiAlH4
AldehydeLiAlH4 1o Alcohol
In order to prevent formation of alcohol, we use a derivative of carboxylic acid ( Acidchloride, Ester and Nitrile ) that is more easily reduced and an derivative of aluminiumhydride ( DIBAL-H ) that is less reactive than lithium aluminium hydride.
AlH
Diisobutylaluminium hydride ( DIBAL-H ) is less reactive than LiAlH4, because
it is much more sterically hindered and ,therefore, have difficulty intransferring hydride ions.
R C NAl H (i-Bu) 2 i.e. DIBAL-H
OH2
R CHO
R C
O
OR1
Nitrile
Ester
Al H (i-Bu) 2 i.e. DIBAL-HOH2
R CHO
R C
O
ClAcid chloride
Al H (i-Bu) 2 i.e. DIBAL-HOH2
R CHO
[3] Preparation of Ketones only
(a) From Acid chlorides
Treatment of acyl chlorides with dialkylcadmium, prepared by the reaction of cadmiumchloride with Grignard reagent, gives ketones.
R Mg X CdCl 2 R2Cd 2 Mg(X)Cl2 + +
R1 C
O
Cl2 + R2Cd R1 CO
R2 + CdCl 2(b) From Nitriles
Treatment of nitrile with Grignard reagent followed by hydrolysis yields a ketone.
R Mg XR1 C N +R1 C
NMgBr
R
OH3+
R1 C
O
R
AROMATIC PORTION(a) From alcohols
CH2
OHK2Cr2O7 / H
+
CHO
C CH3
O
K2Cr2O7 / H+
CH CH3
OH
CH
OH
C
O
K2Cr2O7 / H+
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(b) From acyl chloride ( Rosenmund reduction )
CCl
O
H2
Pd - BaSO 4
CH
O
Benzoyl chloride Benzaldehyde
(c) From nitriles ( stephen reaction )
SnCl 2
HCl
C NCH NH
BenzonitrileImine
OH2 C H
O
(d) From Methyl benzene ( Etard reaction )
CH3
CrO 2Cl 2CS2
+
Toluene
CH ( OCrOHCl 2 )2
Chromyl chloride Chromium complex
CH
O
OH3+
Benzaldehyde
CH3
+ CrO3 ( CH3CO ) 2O+Chromic oxide Acetic anhydride
273 K - 283 KCH ( OCOCH 3 )2
CH
O
OH3+
Benzylidene diacetateToluene
Not Etard reaction
(e) From benzene ( Gatterman - Koch reaction )An aldehyde group is directly introduced by treating benzene with carbon monoxide and
hydrogen chloride in the presence of aluminium chloride as a catalyst.
+ CO HClAlCl 3
+CHO
+ HCl
This is an electrophilic substitution reaction ( modified Friedel-crafts reaction ), wherethe most likely electrophile is acylium ion.
CO + HCl + AlCl 3 C O
H
+ + AlCl 4
(f) From Toluene by side chain chlorination
CH3
Cl2
/ hCHCl 2
373 K
OH2CHO
Benzalchloride
(g) From Grignard reagent
MgBr
R C N+Ether
CCH3
NMgBr
OH3+ C
CH3
O
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Properties of Aldehydes and KetonesNucleophilic Addition Reaction
C O
R1
R2
+ Nu C
Nu
R1O
R2
Slow H
+
FastC
Nu
R1OH
R2
[1] Addition of HCN in presence of a base
C
O
R1 R2 + HCNBase
C
OH
R1 R2
CN Cyanohydrin
Base is used to generate Cyanide ion : HCN + OH CN OH2+
Strong Nucleophile
[2] Addition of Sodium hydrogensulphite
C
O
R1 R2 + NaHSO 3 C
OSO2H
R1 R2
ONa
H+ Transfer C
OSO 2Na
R1 R2
OH
Bisulphite addition product
This bisulphite addition product is formed by all aldehydes and only by methyl ketones.The other ketones due to decrease in electrophilicity of carbonyl carbon and also becauseof steric factors due to alkyl groups, do not react with sodium bisulphite.
This reaction is used to separate and purify aldehydes andketones, because aldehydes and ketones may be recovered from their suphite adducts bywarming them up with sodium carbonate solution.
C
OSO 2Na
R1 R2
OH
Na2CO3C
O
R1 R2 + Na2SO3 NaHCO 3+
[3] Addition of Grignard Reagent
R Mg Br C
O
+ +
C
O Mg Br
R
+
OH2R C OH
Alcohol
+ Mg Br OH
Carbonyl compound
Formaldehyde results in the formation of 1o alcohol
Aldehyde ( Other than Formaldehyde ) results in the formation of 2o alcohol
Ketones result in the formation of 3o alcohol
[4] Addition of AlcoholsAddition of alcohols ( Weak nucleophile ) to aldehydes in acidic medium first formshemiacetals which on addition of second molecule of alcohol results in the formation ofacetals.
Addition of alcohols to ketones to form hemiketals and ketals does not occur readilybecause of the steric hindrance.
R C
O
H R1 OH+H
+R C
OH
OR1
H
R1 OHR C
OR1
OR1
HHemiacetal AcetalAldehyde
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R C
O
R R1 OH+H
+
R C
OH
OR1
R
R1 OHR C
OR1
OR1
RKetone
HemiketalKetal
Alcohol
C O
R
R
CH2
CH2
O
OC
R
R
+ HCl gasdil. HCl
CH2
CH2
OH
OH
Ethyleneglycol ketal
Acetals and ketals are hydrolysed with aqueous mineral acids to yield correspondingaldehydes and ketones.
Nucleophilic Addition - Elimination Reaction
Addition of ammonia and its derivatives
C O
R
R
+ NH2 ZH
+
C N
R
R
Z + OH2
C
O
R R
H+
C
OH
R R+
NH2 Z
x x
C
R
R
OH
N+
H
H
Z H+
C
R
R
OH
N
H
ZOH2
C
R
R
N Z
C O
R
R
H2 NH+Ammonia Imine
C
R
R
N H
C O
R
R
+ H2 NR CR
R
N R
Amine Substituted i mine
( Schiff's base )
C O
R
R
+ H2 NOH
Hydroxyl amine
C
R
R
N OH
Oxime
C O
R
R
+ H2 N NH2 CR
R
N NH2Hydrazone
NHNH
H
Phenylhydrazine
C O
R
R
+ NHNC
R
RPhenylhydrazone
C O
R
R+ NHN
H
HNO2
O2N
NHNC
R
R
NO2
O2N
2, 4 - dinitrophenylhydrazine2, 4 - dinitrophenylhydrazone
( Yellow, Orange or Red solid )
C O
R
R
+ C NH2NH
O
NH
HSemicarbazide
C NH2NH
O
NC
R
R Semicarbazone
Hydrazine
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Reduction Reaction[1] Catalytic Reduction
R C
O
HH2 / Pt ( Primary alcohol )
AldehydeR CH2 OH
R C
O
R H2 / Pt R HC OH
RKetone( Secondary alcohol )
O
OH
H2 / Pt
( Secondary alcohol )
LiAlH4 / NaBH 4
LiAlH4 / NaBH 4
[2] Wolff - Kishner Reduction
C O
R
R
+ H2 N NH2 CR
R
N NH2Hydrazone
Hydrazine
KOH / ethylene glycol
HeatR CH2 R + N2
Alkane
[3] Clemmensen Reduction
R C R
O
Zn - Hg
Conc. HCl +R CH2 RAlkane
OH2
Carbonyl compounds
Oxidation Reaction
R C CH3
O
R C H
O
Ketone
Aldehyde
Strong oxidising agent
Strong oxidising agent
RCOOH HCOOH+
RCOOH
Mild oxidising agent
Mild oxidising agentRCOOH
No product
The oxidation of ketone required cleavage of carbon - carbon bond, which can not break by
mild oxidising agents such as Tollen's reagent and Fehling's solution.
O
Cyclohexanone
Tollen's reagent
Fehling's solutionNo product
K2Cr2O7 / H+
OR KMnO 4 / H+
OR CrO 3 / H+
( CH2 )4
COOH
COOH
Hexanedioic acid ( Adipic acid )Tollen's Test
Aldehyde + Tollen's reagent Silver mirror
Ketone No silver mirror+ Tollen's reagent
To aqueous silver nitrate,a drop of dilute sodium hydroxide is added, forming a brownprecipitate of silver oxide.
Concentrated ammonia is then added until the precipitate just dissolves
So Tollen's reagent is ammonical silver nitrate i.e.
2 AgNO 3 2 NaOH+ Ag2O 2 NaNO 3 OH2+ +
Ag2O + 2 NH 3 NaNO 3+ + OH2 [ Ag ( NH 3 )2 ] NO 3 2 NaOH
+[ Ag ( NH 3 )2 ] NO 3
RCHO 3 OH RCOO 2 H2O 2 e+ + +
[ Ag ( NH 3 )2 ]+
+ e
Ag 2 NH 3+ X 2
RCHO + 3 OH + 2 [ Ag ( NH3 )2 ]+
RCOO + 2 H2O + 4 NH 3 + 2 Ag
Silver mirror
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Fehling's TestFehling solution is a mixture of alkaline copper(II) sulphate solution and sodium poatssiumtartarate (Rochelle salt ) Aldehyde + Fehling's reagent
Ketone + Fehling's reagent No Reddish Brow n precipitateReddish Brow n precipitate
Aromatic aldehyde + Fehling's reagent No Reddish Brow n precipitate
RCHO 3 OH RCOO 2 H2O 2 e+ + +
2 Cu 2 OH Cu2O OH2++ 2 e
+
2+
RCHO + 2 Cu2+
+ 5 OH
RCOO
+ 3 H2O + Cu2O Reddish Brown precipitate
Hydroxyketones give positive Tollen's and Fehling test, because inhydroxyketones,thesecondary alcoholic group gets oxidised to ketonic group.
CH3 CH2 CH
OH
C CH3
O3-Hydoxypentan- 2-one( hydroxyketone )
CH3 CH2 C
O
C CH3
OPentane- 2, 3 - dione
+Fehling's reagentTollen's reagent
2 H2O + 4 NH 3 + 2 AgSilver mirror
3 H2O
+Cu
2O
Reddish Brow n precipitate
Idoform TestThe reaction is used to detect the and groups in an organiccompound. The organic compounds containing the above groups when treated withhalogen in presence of an alkali results in the formation of Chloroform,bromoform oridoform. Idoform is a yellow solid.
CH3 C
O
CH3 CH
OH
R C CH3
O
+ NaOIsodium hypoiodite
i.e. I 2 & NaOHR C
O
ONa + CHI 3 Idoform( Yellow ppt. )
CH3CH
OH
R + I2 2 HI
CH3C
O
R+I2 NaOH
R C
O
ONa + CHI 3 Idoform( Yellow ppt. )
This oxidation does not affect a carbon- carbon double bond, if present in the molecule.
CH3 CH C
CH3
C CH3
O
+ NaOIsodium hypoiodite
CH3 CH C
CH3
C
O
ONa + CHI 3 Idoform( Yellow ppt. )
The iodoform reaction is given by:
(1) Ethanol [ The only 1o alcohol ]
(2) All secondary alcohols with group. (3) Acetaldehyde [ the only aldehyde ]CH3 CH
OH
CH3 C
O
CH3 C
O
group is necessary for idoform reaction, because the group is an
electron withdrawing group, which makes the H of methyl group acidic in nature.
C
O
The conjugate base, after removal of H, become resonance stabilised.
C CH
O
H B C CH
O
C CH
O
(4) All methyl ketones [ aliphatic and aromatic ] with group.
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Aldol condensationAldehydes and ketones having at least one H undergo a reaction in presence of dilutealkali as catalyst to form hydroxy aldehydes or hydroxy ketones
[ ALDOL = ALD ehyde + alcoh OL ]
2 CH 3CHOdil NaOH
CH3 CH CH2 CHO
OH
OH2
CH3 CH CH CHO
3 -Hydroxybutanal [ Aldol ] But-2-enal
CH3 C
O
H
H CH2 C H
O
+dil NaOH
CH3 CH CH CHO
OH H
OH2
CH3 CH CH CHO
CH3 C
O
CH3
H CH2 C CH3
O
+dil NaOH
CH3 C CH C
OHH
O
CH3
CH3
OH2
Ethanal
CH3 C CH3
OBa(OH) 2
2 CH3 CH CH2 C
OH
CH3
O
CH3
OH2CH3 C CH C
CH3
O
CH3
Propanone
4-Hydroxy- 4-methylpentan- 2-one
4-Methylpent- 3-en- 2-one[ Ketol ]
CH3 C CH C
CH3
O
CH3
When aldol condensation is carried out between two different aldehydes or ketones, it is
called cross aldol condensation.
CH3CHO
CH3CH2CHO
1. NaOH
2. +
CH3 CH CH CHO + CH2 CH C CHOCH3
CH3
Selfcondensationproduct
H3C CH C CHO
CH3
+ CH2 CH CH CHOCH3MixedcondensationproductPent- 2-enal2-Methylbut- 2-enal
But- 2-enal 2-Methylpent - 2-enal
C
O
H
CCH2
O
H
Benzaldehyde
No hydrogen
+
Acetophenone
Having hydrogen
CH
OH
CH
H
C
O
CH CH C
O
dil NaOH
OH2
1,3-diphenylprop-2-en-1-oneCannizzaro Reaction
Aldehydes having nohydrogen,when treated with conc. alkali, undergo self oxidationand reduction [ disproportionation / dismutation / auto oxidation-reduction ] reaction.
H C H
O
2 Conc. NaOH CH3OH HCOONa+Methanal Methanol Sodium methanoate
C
O
HConc. NaOH
2
Benzaldehyde
CH2 OH C
O
ONa+
Benzyl alcohol Sodium benzoate
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Electrophilic substitution reaction.Carbonyl groups act as deactivating and meta - directing group.
C
OR
R = H : aldehydeR = alkyl : Ketone
Cl 2 / AlCl 3
HNO 3 / H2SO4
H2SO4 / SO 3
C
O
R
Cl
C
O
R
NO2
C
O
R
SO3H
40%solutionofform
aldehydeisknownasform
alin.
ALIPHATIC PORTION
Preparation of Carboxylic Acids[a] From alcohol and aldehyde
R C H
O
RCH 2OH RCOOH1. alkaline KMnO 4
2. H3O+
1o alcohol
CH3 (CH2)8CH2OH
1-Decanol
CH3 (CH2)8COOH
Decanoic acid
1. alkaline KMnO 4
2. H3O+
Aldehyde
RCOOHStrong oxidising agent
Mild oxidising agentOR[b] From Grignard reagents
C O
O
R MgBr +- +
RC
O MgBr
O
Dry etherH3O
+
RCOOH
Dry ice
- +
[c] FromAcid derivatives
Acid chloride
Acid anhydride
Ester
Amide
R C
O
ClOH2
ClH+RCOOH
R C
O
OC R1
O
OH2RCOOH + R1COOH
R C
O
OR' RCOOH R' OH+H3O
+NaOH
RCOONa R' OH+H3O
+
RCOOH( Saponification)
R C
O
NH2
H3O+
RCOOH + NH3R C N
Nitrile
H3O+
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AROMATIC PORTION
CH2 R
Alkyl benzene
KMnO 4 - KOH
COOKH3O
+ COOH
[ The entire side chain is oxidised to the carboxylic acid irrespective of length of side chain ]
CONH 2
Benzamide
H3O+
COOH
NH3+
C
O
OC
CH3
O
H3O+
OH2
Benzoic ethanoic anhydride
COOH
+ CH3COOH
Benzoic acid
Benzoic acid
Benzoic acidEthanoic acid
C
O
OC2H5
Ethyl benzoate
COOH
+ C2H5OH
Properties of Carboxylic Acid[1] Acidity
Carboxylic acids dissociate in water to give resonance stabilised carboxylate anion.
R C
O
OH + OH2 R CO
O
R C
O
O
+ H3O+
2 RCOOH + 2 Na 2 RCOONa H2+
RCOOH NaOH+ RCOONa OH2+RCOOH + NaHCO 3 RCOONa + OH2 + CO2 [ Test for carboxylic group ]
[ Brisk effervescence ]
CH2 CH COOH CH3 CH2 COOHAcidity of >
SP2
SP3
C
O
OH CH2
C OH
O
>
SP2
SP3
carbon is more electronegative than carbon,SP2 SP3
[2] Esterification
CH3 C OH
O
H O CH3+Acid Alcohol
CH3 C O
O
CH3H
+
+ OH2Ester
CH3 C OH
O
+ OHH
+
OC
O
CH3 + OH2Phenyl ethanoateEthanoic acid Phenol
The water should remove from the mixture, because ester may undergohydrolysis.
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H2SO4 /
or P2O5 /
[3] Formation of Acid anhydride
CH3 C
O
OHC CH3
O
OH
CH3 C
O
O
C CH3
O
+
Ethanoic acid Ethanoic anhydride
+ OH2
[4] Formation of Acid chloride
CH3 C
O
OH PCl 5
PCl 3
SOCl 2
+ClHPOCl 3CH3 C
O
Cl + +
CH3 C
O
OH3 + CH3 C
O
Cl3 + H3PO 3
CH3 C
O
OH + CH3 C
O
Cl + SO2 + ClH
[5] Formation of Acid amide
CH3 C
O
OH + NH3 CH3 C
O
O NH4+
CH3 C
O
NH2
Ammonium ethanoate Ethanamide
COOH
+ NH3COO NH 4
OH2
OH2
CONH 2
Amm.benzoate Benzamide
COOH
COOH
+ NH3 COO NH4
COO NH4
- +
- + 2 H2O
CONH2
CONH2
Strong heating
C
C
NH
O
OPhthalic acid Ammonium phthalate Phthalamide
Phthalimide
NH3
[6] Formation of Alcohol [ Reduction ]
R C
O
OH
LiAlH4 / Ether
H3O+
R CH2 OH[ The reaction involve hydride transferand causes reuction of carbonyl group ]
R C
O
OHH3O
+
B2H6R CH2 OH
[ Diborane is better for this process, becauseit does not easily reduce ester,nitro and halogroups]
Sodium borohydride does not reduce the carboxyl group.[7] Formation of Alkane [ Decarboxylation ]
R C
O
ONa + NaO H
CaORH + Na2CO3
AlkaneSodium salt of carboxylic acid
[ NaOH & CaO in the ratioof 3:1 is known as sodalime ]
Kolbe electrolysis
RCOONaElectrolysis
R R + CO2 + NaOH H2+At anode At cathode
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[8] Hell - Volhard - Zelinsky Reaction ( HVZ reaction )
R CH2 COOH
Having - hydrogen
(i) X2 / Red phosphorous
(ii) H 2O
R HC COOH
X
X : Cl , Br
If two hydrogens are present, both of them may be substituted by halogen.
[9] Ring substitution reactionCarboxylic group act as deactivating and meta directing group.
C
OHO
Cl 2 / AlCl 3
HNO 3 / H2SO4
H2SO4 / SO3
HOOC
Cl
HOOC
NO2
HOOC
SO3H
ExplanationsDue to polarity of carbonyl group to ward oxygen,the intermolecular association of carbonylcompounds occurs which makes the boiling point of carbonyl compounds higher than the
corresponding alkane of comparable mass.However carbonyl compounds can not form hydrogen bonding with
each other and their boiling points are lower compared to alcohol (of comparable mass)
The lower members of aldehydes and ketones are soluble in water in all proportions,because they associate with water molecules through hydrogen bonding.
The reaction of Grignard reagent with nitriles is considered to be the best method for thepreparation of carbonyl compounds, because, in the first stage of addition an imine isformed as an intermediate product. The imine is then isolated and hydrolysed to give acarbonyl compound as the final product.
Reaction of Grignard reagent with acid chloride and esters produce carbonylcompounds,but the reaction does not stop at this stage and proceeds further with another
molecule of Grignard reagent to give corresponding alcohol as the final product.Grignard reagent and dialkyl cadmium both are organometallic compounds, but reaction ofacid halides with[a] Grignard reagent is not satisfactory method for the preparation of ketones.[b] Dialkylcadmium is a satisfactory method for the preparation of ketones.Because, in case of dialkylcadmium, due to less reactivity of cadmium, reaction with acidchloride occurs only upto the formation of ketone. The reaction of Grignard reagent doesnot stop after formation of ketone, since magnesium is more reactive metal,and proceedsfurther to form tertiary alcohol.
Aryl ketones do not undergo addition of alcohol to form hemiacetals and ketals because ofsteric factor.
CR
O
+ R' OH
R = alkyl / aryl
H
+
No reaction
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Aryl ketones do not give addition product with sodium bisulfite due to steric factor.
C R
O
+ NaHSO 3 No reaction
R = alkyl / aryl
The order of reactivity of aldehydes and ketonestoward nucleophilic addition reaction: C
O
H HC
O
R HC
O
R R
Sterically the presence of two relatively large substituents in ketones hinder the approachof nucleophile to carbonyl carbon than in aldehydes.
Electronically two alkyl groups in ketone reduce the electrophilicity of the carbonylmore effectively than in aldehyde.
NH2 NH C
O
NH2x xx x
[Semicarbazide]
Involved in the formationof semicarbazone
The right side -NH2 group is in conjugation with electron
withdrawing carbonyl group and acquires positive charge and notin a position to act as the nucleophile, so does not involvein the formation of semicarbazone.
O
Cyclohexanone
OH
CN
O
CH3 CH3
CH3
HCNHCN No product
cyanohydrin
2, 4, 6-trimethylcyclohexanoneIn 2,4,6-trimethylcyclohexane, the three methyl groups will increase the electron densityon the carbonyl carbon atom and the nucleophile attack does not seem to be feasible.Moreover,the two methyl substituents at the ortho position will also hinder the attack of
nucleophile CN ion on the carbonyl group.
Upon heating , formic acid loses a molecule of water and gets dehydrated to give carbonmonoxide. Therefore it does not form anhydride upon heating.
HCOOH H2OCOHeat
+Phenoxide ion has more number of resonating structures than carboxylate ion, butcarboxylic acid is a stronger acid than phenol. Because, in carboxylate ion the negative
charge is dispersed on two electronegative oxygen atoms while incase of phenoxide ion,there is only one oxygen atom to disperse the negative charge.
Benzaldehyde and other aromatic aldehydes form silver mirror with Tollen's reagent butfail to react with fehling's solution and Benedict's solution. Due to resonance, the electrondensity on the carbonyl carbon atom inbcreases, as a result the CH bond becomesstronger. It can be oxidised to C OH with strong oxidising agents like Tollen's reagent
( EoAg2+|Ag = +0.8 V ) but not with weaker Fehling's or Bendedict's reagent
( Eo Cu2+ |Cu = +0.34 V )
In Fehling solution , copper sulphate forms a soluble complex of Cu2+ ions with tartarate
ion of the Rochelle's salt. The complex provides the Cu2+ ions and also checks the
precipitation of copper hydroxide in the reaction.
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Class-XII AldehydesKetonesCarboxylic Acids
Jayanta kumar sahuPGT : ChemistryKendriya Vidyalaya Sangathan Page - 14
Predict the ProductsOH
PCC , CH 2Cl 2O
Cyclohex- 2-en- 1-ol? Cyclohex- 2-en- 1-one
+ H5C2C
O
Cl ?Anhy. AlCl 3
CS2
( C6H5CH2)2Cd 2 CH3COCl+ ?CH3 C CH
Hg2+
H2SO4 ?CH3 NO2
1. CrO 2Cl 2
2. H3O+ ?
CC2H5
O
CCH3
O
CH2
CH3
C
CH3
O
OHC NO2
OHONH 2
H+
?+
O
NH NO2
O2N
NH2+ ?
R CH CH CHO NH2 C
O
NH NH2+ H+
?C
CH3
O
CH3CH2NH2+ H+
N OH
NH NO2
O2N
N
R CH CH CH N NH C
O
NH2
C
CH3
N CH2CH3
?
CH2 CH3KMnO 4
KOH , Heat ?
COOH
COOH
SOCl 2
Heat ?
CHONH2 C
O
NH NH2 ?O
CHO
[ Ag(NH 3)2]+
?
COOK
COCl
COCl
N NH C
O
NH2CH
O
COO
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Class-XII AldehydesKetonesCarboxylic Acids
Jayanta kumar sahuPGT : ChemistryKendriya Vidyalaya Sangathan Page - 15
CHO
COOH
NaCN / HCl
?
C6H5CHO CH3CH2CHOdil. NaOH+ ?
CH3COCH 2COOC 2H5(i) NaBH 4
(ii) H+
OHCrO3
?
?
COOH
CH
OH
CN
H5C6 CH C
CH3
CHO
CH3 CH
OH
CH2 COOEt
O
(i) O3
(ii) Zn - H 2O
O
?
CHO
+ C6H5MgBrH3O
+ CHC6H5
OH
?
[ Ag(NH 3)2]+
OH-
CHO
+ + ?COO
-
CHO
+ NH2 C
O
NH NH2 ?CH NHCONH 2
C O
H
H OC 2H5+
H OC 2H5 ? CH
OC2H5
O C2H5
O
+dil. NaOH
OH
O
?
O
O
O
Raney Ni / H 2
NaBH 4 / CH 3OH
OH
?
?OH
CH C6H5(i) O3
(ii) Zn / H 2O?
O
C6H5CHO+
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