7/24/2019 Aldehyde and Ketone Reactions Ppt
1/21
Aldehyde & Ketone
Reactions
7/24/2019 Aldehyde and Ketone Reactions Ppt
2/21
Formation of an AldehydeOxidation of Primary Alcohols
General equation:
Primary alcohol aldehyde
RCH2CHO
!"A#P$!:
%'ro'anol
7/24/2019 Aldehyde and Ketone Reactions Ppt
3/21
Formation of a KetoneOxidation of (econdary Alcohols
General equation:
(econdary alcohol )etone
O
RCR
!"A#P$!:
2'ro'anol
C
O
RH
R
H [ O ]
7/24/2019 Aldehyde and Ketone Reactions Ppt
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Re*ie+ from Cha'ter %,--Oxidation of .ertiary Alcohols
General equation:
.ertiary alcohol /OR!AC.0O/---
7/24/2019 Aldehyde and Ketone Reactions Ppt
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1O .R1 .H!(!-
3rite an equation sho+in4 theoxidation of the follo+in4 alcohols56e sure to name the 'roduct formed5
7a8 %'entanol
798 29utanol
7/24/2019 Aldehyde and Ketone Reactions Ppt
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Oxidation of Aldehydes
Aldehydes are easily oxidied furtherto form car9oxylic acids5
Oxidation 'rocess:
Primary alcohol Aldehyde Car9oxylic acid
1-butanol
2-methyl-1-propanol
[ O ] [ O ]
[ O ] [ O ]
7/24/2019 Aldehyde and Ketone Reactions Ppt
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Reduction Reactions
6oth aldehydes and )etones areeasily reduced 9ac) to thecorres'ondin4 alcohol5 .his 'rocess
is called hydrogenation5
RR
7/24/2019 Aldehyde and Ketone Reactions Ppt
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$a9 .ests for
Aldehydes and Ketones
Tollens Test
.ests for A$;!H1;!( 7not )etones8
(il*er ion is reduced to sil*er metal
.he aldehyde is oxidied to acar9oxylic acid anion
AKA the (il*er #irror .est
7/24/2019 Aldehyde and Ketone Reactions Ppt
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.ollen
Aldehyde sil*er ammoniacar9oxylic sil*er
com'lex acid anion
metal ? < @
7/24/2019 Aldehyde and Ketone Reactions Ppt
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3rite equations for the follo+in4reactions
%5 ethanal = .ollen
7/24/2019 Aldehyde and Ketone Reactions Ppt
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6enedict
7/24/2019 Aldehyde and Ketone Reactions Ppt
12/21
6enedict
7/24/2019 Aldehyde and Ketone Reactions Ppt
13/21
6enedict
7/24/2019 Aldehyde and Ketone Reactions Ppt
14/21
Addition Reactions05 Addition of an Alcohol to an Aldehyde Acetal
formation
O H H= OH H
R%CH = OR2 R%COR2 = OR2 H
Aldehyde alcohol Hemiacetal7quite reacti*e8
OR2
H+ R1-C-OR2
HAcetal
7/24/2019 Aldehyde and Ketone Reactions Ppt
15/21
Addition Reactions
OR 4rou' is an al)oxyl 4rou'
Hemiacetalsare *ery reacti*e so inthe 'resence of acid and excessalcohol +ill continue to react to forman acetal
7/24/2019 Aldehyde and Ketone Reactions Ppt
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Addition Reactions
25 Addition of an alcohol to a ketoneB KETALformation
O H OH H
R%CR2 = OR, H= R%COR, = OR,
R2Ketone alcohol Hemiketal
OR,
H= R%COR,
R2 Ketal
7/24/2019 Aldehyde and Ketone Reactions Ppt
17/21
Practice Pro9lems
Pro'anal = #ethanol
,hexanone = ethanol
7/24/2019 Aldehyde and Ketone Reactions Ppt
18/21
Keto!nol .automers
#any aldehydes & )etones exist in amixture of t+o constitutionalisomers informally referred to as
tautomers5R1
R2 R3
O R1
R2
R3
OH
Keto form Enol form
7/24/2019 Aldehyde and Ketone Reactions Ppt
19/21
Practice
;ra+ the enol form of the aldehydesand )etones listed 9elo+5 !thanal
2'entanone
6utanal
7/24/2019 Aldehyde and Ketone Reactions Ppt
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Aldol Condensation
Reaction in +hich aldehydes &)etones react to form lar4ermolecules5 A ne+ car9oncar9on
9ond is formed in the 'rocess5
Actually occurs 9et+een an aldehydein the )eto form and one in the enolform5
R1
O
R2
O
+
O H - o r
e n z y m e
R1
OH O
R2
Aldehyde Aldehyde Aldol
7/24/2019 Aldehyde and Ketone Reactions Ppt
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!xam'le
3rite an equation for the aldolcondensation of t+o molecules of9utanal5
O OH+
OH O
Butanal
Butanal (enol form)
3-
hydroy-
2-
ethylheanal