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Solutions for Condensations and Alpha Substitutions of Carbonyl Compounds
H
H
O
C
O
H
HO
H
O
OH
H
O
HHO
O
O
H
O
18
In general, the equilibrium in aldol condensations of ketones favors reactants rather than products. There is 
significant steric hindrance at both carbons with new bonds, so it is reasonable to conclude that this reaction 
of cyclohexanone would also favor reactants at equilibrium.
H
OOH OH
Ph
O
Ph
H
19 New carbon-carbon bonds are shown in bold.
(a) (b)
O
(c) HO
CO3
2–
C
CH3
CH3
OCH3 C
O
CH2 C
CH3
CH3
O
H
C O
CH3
CH3
CH2C
O
CH3
CH3 C
O
CH2C CH2
O
CH3CH3 C
O
CH2
H
20 All the steps in the aldol condensation are reversible. Adding base to diacetone alcohol promoted the 
reverse aldol reaction. The equilibrium greatly favors acetone.
+
H OCO2
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