Industrial Biotransformations

3.15
a-Hydroxy Ketones
R
R 1
R
OH
O
OH
OH
O
O
R'
R 2
OH
acyloin reaction
+
R3
O
H
decarboxylase
lyase
decarboxylase
transketolase
3.15 a-Hydroxy Ketones
The classic method to prepare some of these compounds is to use decarboxylative acyloin
reactions (a type of aldolase reaction) [47].
The dynamic resolution of 2-hydroxy ketones has been reported using whole cell systems
where two different alcohol dehydrogenases with complementary enantioselectivity
are involved [48]. For this particular example, the enantioselectivity is pH dependent.
O
OH
pH 4.0-5.0
pH 7.5-8.5
O
O
OH
OH
R'
R
R2
R
O
O
O
O
H
H
H
+
+
+
+
R'
R'
R 1
OH
O
O
O
O
O
OH
O
79
OH
R3
OH