2
Tetrahedron Letters
Whole cell biocatalysis in an organic solvent has a limitation
due to the toxic effect of the solvent on the enzyme activity. On
the other hand, organic solvents may absorb inside the cell
membrane leading to a change in membrane fluidity and ease in
substrate uptake resulting in activity retention.
O
OH
Plant tissue
isooctane
(
-
S) alcohol
Scheme 1.
The biotransformation of trans-4-phenylbut-3-en-2-one into
The bioreductions in isooctane in the presence of carrot
Daucus carota L.), celeriac (Apium graveolens L. var.
rapaceum) and beetroot (Beta vulgaris L. subsp. Vulgaris)
proceeded in good to excellent yields. The highest yield was
achieved with carrot (96%), and were lower with celeriac (78 %)
and beetroot (71%).
(
trans-4-phenylbut-3-en-2-ol using plant tissue, has already been
observed in the reaction catalyzed by the beans of Vigna
5
unguiculata. In this case, the double bond was mainly reduced,
resulting in the formation of 4-phenylbutan-2-one. The product
of the exclusive reduction of the C=O bond was observed in only
trace amounts (3%). On the other hand, reduction of
cinnamaldehyde with coconut juice occurred selectively at the
carbonyl group to yield the corresponding alcohol (84%) without
All the selected plants reduced trans-4-phenylbut-3-en-2-one
to (S)-trans-4-phenylbut-3-en-2-ol with high enantioselectivity
(Table 1). The reduction occurred only at the carbonyl group.
Bioreduction of the carbonyl group by carrot and celeriac enzyme
12
affecting the double bond.
1
systems is well documented and proceeds enantioselectivity,
Healthy and ripe roots of carrot (Daucus carota L.), celeriac
Apium graveolens L. var. rapaceum) and beetroot (Beta vulgaris
following Prelog’s rule, which results in the formation of (S)-
alcohols predominantly.
(
L. subsp. Vulgaris) were selected for this biotransformation.
These vegetables are accessible in all seasons and have the
advantage of low cost. The reaction procedure is very simple: to
a stirred suspension of comminuted plant tissue (330 g) in
isooctane (600 ml). trans-4-phenylbut-3-en-2-one (1.5 g) was
added at 25 ˚C. Aliquots were withdrawn periodically and the
progress of the reaction was monitored by means of TLC and
GC. After three days, we observed the maximum percentage
yield and the plant residue was filtered off. The organic phase
In conclusion, the regio- and stereoselective reduction of
trans-4-phenylbut-3-en-2-one with comminuted roots of the
popular vegetables such as carrot, celeriac and beetroot in
isooctane can be viewed as a further useful tool for organic
chemists by virtue of the simplicity. The encouraging results
obtained here may offer new possibilities for the reduction of
selected , -unsaturated carbonyl compounds that are insoluble in
water, as a critical step in a synthetic organic pathway,
specifically avoiding the use of non-sustainable, hydride reducing
agents.
was dried over MgSO
4
, the isooctane was evaporated and the
crude residue was purified by flash column chromatography. The
1
13
structure of the product was confirmed by H NMR and FT-IR.
The enantiomeric excesses of the products were determined by
measuring specific rotations and calculated as follows:
References and notes
ee (%) = ([α]observed / [ ]maximum) x 100
1
.
a) Baldassarre, F.; Bertoni, G.; Chiappe, C.; Marioni, F. J. Mol.
Catal B: Enzym. 2000, 11, 55-58; b) Bruni, R.; Fantin, G.; Medici,
A.; Pedrini, P.; Sacchetti, G. Tetrahedron Lett. 2002, 43, 3377-
The biotransformation of trans-4-phenylbut-3-en-2-one
was also carried out in polar solvents such as water and
acetonitrile (Table 1). A water-miscible organic solvent was
thought to aid in the solubility by the phenomenon of co-
solvency, however, water-immiscible organic solvents aid by
forming a biphasic reaction mixture. In the cases of water and
acetonitrile no reaction was observed, probably due to the
insolubility of the substrate in polar solvents.
3
379; c) Mączka, W. K.; Mironowicz, A. Tetrahedron:
Asymmetry 2002, 13, 2299-2302; d) Utsukihara, T.; Watanabe, S.;
Tomiyama, A.; Chai, W.; Horiuchi, C. A. J. Mol. Catal B: Enzym.
2
006, 41, 103-109; e) Cordell, G. A.; Lemos, T. L. G.; Monte, F.
J, Q.; de Mattos, M. C. J. Nat. Prod. 2007, 70, 478-492; f) Xie, B.;
Yang, Q.; Yuan, W. J. Mol. Catal B: Enzym. 2009, 61, 284-288 g)
Liu, X.; Pan, Z. G.; Xu, J. H.; Li, H. X. Chin. Chem. Lett. 2010,
2
1, 305-308; h) Liu, X.; Wang, Y.; Gao, H. Y.; Xu, J. H. Chin.
Chem. Lett. 2012, 23, 635-638; i) Zilinskas, A.; Sereikaite, J. J.
Mol. Catal B: Enzym. 2013, 90, 66-69.
Olejniczak, T.; Mironowicz, A.; Wawrzeńczyk, C. Bioorg. Chem.
2003, 31, 199-205.
Table 1. Reduction of trans-4-phenylbut-3-en-2-one with
plant tissue
2
.
a
3
.
a) Mączka, W. K.; Mironowicz, A. Z. Naturforsch. 2007, 62c,
3
97-402; b) Vandenberghe A., Markó, I. E.; Lucaccioni, F.; Lutts,
Plant
Solvent
S-Alcohol
S. Ind. Crops Prod. 2013, 42, 380-385.
b
4.
Andrade, L. H.; Utsunomiya, R. S.; Omori, A. T.; Porto, A. L. M.;
Comasseto, J. V. J. Mol. Catal B: Enzym. 2006, 38, 84-90.
Bizerra, A. M. C.; Gonzalo, G.; Lavandera, I.; Gotor-Fernández,
V.; de Mattos, M. C.; da Conceicão F. de Oliveira, M.; Lemos, T.
L. G.; Gotor, V. Tetrahedron: Asymmetry 2010, 21, 566-570.
Lumbroso, A.; Cooke, M. L.; Breit, B. Angew. Chem. Int. Ed.
Yield (%)
ee (%)
5
6
.
.
carrot
2
H O
-
-
-
carrot
MeCN
-
carrot
isooctane
96
-
>99
-
2
013, 52, 1890-1932.
celeriac
celeriac
celeriac
beetroot
beetroot
beetroot
a
H
2
O
7.
Fehr, C.; Galindo, J. Angew. Chem. Int. Ed. 2000, 39, 569-573.
Burgess, K.; Jennings, L. D. J. J. Am. Chem. Soc. 1991, 113,
8
.
MeCN
-
-
6
129-6139.
9
1
.
Noyori, R.; Ohkuma, T. Angew. Chem. Int. Ed. 2001, 40, 40-73.
isooctane
78
-
98
-
0. Hage, A.; Petra, D. G. I.; Field, J. A.; Schipper, D.; Wijnberg, J.
B. P. A.; Kamer, P. C. J.; Reek, J. N. H.; van Leeuwen, P. W. N.
M.; Wever, R. E.; Schoemaker, H. Tetrahedron: Asymmetry 2001,
2, 1025-1034.
1. Ghanem, A.; Schuring, V. Tetrahedron: Asymmetry 2003, 14, 57-
2.
2
H O
MeCN
-
-
1
1
isooctane
71
72
6
12. Fonseca, A. M.; Monte, F. J. Q.; da Conceicão F. de Oliveira, M.;
de Mattos, M. C.; Cordell, G. A.; Braz-Filho, R.; Lemos, T. L.G.
J. Mol. Catal B: Enzym. 2009, 57, 78-82.
Reduction over 3 days.
a
Determined by GC analysis.
1
3. Analytical methods: