organic solution mj
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1.
When two moles of oxaldehyde are heated with NaOH, they undergo intermolecular cannizaro
reaction to give equimolar amounts of corresponding alcohol and the salt of carboxylic acid.
2.
Compound
O
O
react with 2 moles of Grignard reagent to giveOH
OH
OO CH3MgBr
O OO
O1. CH3MgBr
2. H3O
OH
3.
CH3CH2CHO contain alpha hydrogen, when treated with NaOH; undergo aldol condensation
reaction to give alpha-beta unsaturated aldehyde.
4.
Two moles of cyclohexanone undergo aldol condensation reaction to give alpha-beta
unsaturated ketone.
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O
OH
O
O
OHO
H2O -H2O
O
5.
A is CH3CO2C2H5, an ester, containing alphahydrogen, when treated with strong base NaOC2H5
(B) undergo Claisen condensation reaction to give beta-keto ester which when hydrolysis form
beta-keto acid, which easily decarboxilate on heating to give acetic acid.
6.
When CH3CH = CHCHO is treated with NaOH , proton abstraction take place from methyl group
which is more acidic centre, and then undergo aldol condensation reaction.
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7. When CH3CH2OCOOCH2CH3is treated with two moles of methyl magnesium bromide form acetone.
The compound containing CH3CO- group gives positive iodoform test.
So acetone gives a ppt. of CHI3and carboxilate ion.
Acetone can also be obtained by ozonalysis of 2, 3-dimethyl-2-butene.
Further addition of methyl magnesium bromide gives tertiary alcohol after hydrolysis.
O O
O
CH3MgBr O O
OBrMg
O
O
CH3MgBr
O
OBrMgO
Acetone
O
CH3MgBr O
MgBrOHH3O
OzonalysisO O+
8. Under the influence of dilute base two molecules of aldehyde or ketone containing at least one alpha-
hydrogen undergo aldol condensation reaction.
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Compound
HC
CH3
CHO
contains alpha-hydrogen undergo aldol condensation reaction.
9. When Ethyl acetate is treated with ethoxide ion gives Claisen condensation product is Ethyl aceto
acetate (E.A.A) which gives positive iodoform reaction.
H3C C OEt
OOH
EtO C
O
CH2 OEtC
O
H3C+
EtO C
O
CH2 C OEt
O
CH3
EtO C
O
CH2 C CH3
O
When treated with NH2OH gives oxime.
EtO C
O
CH2 C CH3
O
+ NH2OH EtO C
O
CH2 C CH3
N
OH
E.A.A also undergo totomerisation
EtO C
O
C CH3
O
H
EtO C
O
CH2 C CH3
O
10.
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C NH2
OP5O10
NCH3MgBr
H3OC CH3
O
Ca(OH)2I2
C OH
O
+ CHI3Heat
A B
CD
11. When R-CO-NH2is treated with alkaline solution bromide undergoes Hofmann rearrangement
thorough following intermediates.
C NH2
O
ROH
C NH
O
RBr Br
C NHBr
O
R
C NBr
O
R
H OH
C NBr
O
R C
N
O
R Br -Br
R shiftR N C O
.
12. An unstable amide undergoes Hofmann degradation reaction when treated with alkaline solution
bromide. So CH3CONH2will show Hofmann degradation reaction.
13. A beta-keto acid decarboxilate readily on heating because the activation energy of this
decarboxilation, which involves a stable six-member cyclic transition state.
O OH
OH
O O
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14. Cyclohexanone, when treated with Ethyl aceto acetate in presence of ethoxide ion form
O O
O O
H3C C OEt
O O O
OEt
O O
OEt
15. Compound
H3C C O
OHC
CH3
Et*
undergoes hydrolysis through BAL1 mechanismwhere configuration of chairal carbon is retained.
H3C C O
OH
C
CH3
Et
Slow
H3C C O
O
+ HC
CH3
Et H2O
H3C C O
O
+ HC
CH3
Et
OH2
fast
H3C C OH
O
+ HC
CH3
Et
OH
*
*
**
16. When compound H3C CH2
C
H2
C C
H2
C CH3
O O
O is treated with one mole of ethyl
magnesium bromide form
O
OH3C
C2H5
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H3C C
H2C
H2C C
H2C CH3
O O
O
C2H5MgBr
H3OH3C C
H2C
H2C C
H2C CH3
OH
O
C2H5 O
O O
OCH2CH3
H3C
C2H5
OO
H3C
C2H5
17. When Ethyl acetate is treated with ethoxide ion undergoes Claisen condensation reaction to give
ethyl aceto acetate (E.A.A) which gives positive iodoform reaction.
H3C C OEt
OOH
EtO C
O
CH2 OEtC
O
H3C+
EtO C
O
CH2 C OEt
O
CH3
EtO C
O
CH2 C CH3
O
Enolic form of E.A.A decolorize Br2solution due presence of unsaturation
EtO C
O
C CH3
O
H
EtO C
O
CH2 C CH3
O
EtO C
O
CH
C CH3
OAc
EtO C
O
CH C CH3
OH
Br Br
Br2
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Enolic form of E.A.A also undergoes acylation when treated with acetic anhydride.
EtO C
O
C CH3
O
HAc2O
EtO C
O
CH
C CH3
OAc
18. Alkaline hydrolysis is maximum where the -NO2 group is at para position of the benzene ring,
because the electrophilicity of carbonyl carbon increases due toR effect of the -NO2 group.
19. Compound (I) is stabilized by the +R effect of OMe group whereas compound (II) is stabilized by
hyperconjugative effective of CH3 group (structre I). So (I) is most stable. In compound (III) positive
charge is delocalized into the phenyl ring only show less stability than previous compounds but more
stable than (IV) where positive charge is stabilized by only +I effect of methyl group.
20. Compound 3 is more stable as radical is fully delocalized into phenyl ring.
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21. Most stable radical is compound 4 as more delocalization of radical.
22. Most stable carbocation is compound 3 as positive charge is fully delocalized into phenyl ring.
23. Due to more electron density at Para position with respect to the -OCOPH group of the phenyl ring
electrophilic attack of -NO2group takes place at Para position of the phenyl group.
24. In compound (I) radical is stabilized by +R effect of phenyl ring whereas in compound (III) radical is
stabilized by three +I effect of methyl groups
In compound (II) radical is stabilized by hyper conjugation effect only and more than compound (IV).
So the order of stability is (IV) < (II) < (III) < (I).
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25. In SN2 fashion neucleophilic attack and leaving group departure occur simultaneously with inversion
of configuration of product.
C ClH
CH3
CH2CH3
C HCl
CH2CH3
CH3
OHC
H
Cl
CH2CH3
CH3
OH
C
H
CH2CH3
H3C Cl
C OHH
CH3
CH2CH3
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