Cascade bio-hydroxylation and dehalogenation for one-pot enantioselective synthesis of optically active β-halohydrins from halohydrocarbons

Article abstract of DOI:10.1039/c9gc01802f

A stereoselective hydroxylation and enantioselective dehalogenation cascade reaction was developed for the synthesis of optically active β-haloalcohols from halohydrocarbons. This cascade system employed P450 and halohydrin dehalogenase as two compatible biocatalysts, allowing a straightforward, greener and efficient access to β-halohydrins with excellent enantioselectivities (98-99%).

Full text of DOI:10.1039/c9gc01802f

View Article Online
View Journal
Green
Chemistry
Cutting-edge research for a greener sustainable future
Accepted Manuscript
This article can be cited before page numbers have been issued, to do this please use: H. Cui, L. Xie, N.
Wan, Q. He, Z. Li and Y. Chen, Green Chem., 2019, DOI: 10.1039/C9GC01802F.
Volume 20
This is an Accepted Manuscript, which has been through the
Number
May 2018
Pages 1919-2160
9
7
Royal Society of Chemistry peer review process and has been
accepted for publication.
Green
Chemistry
Cutting-edge research for a greener sustainable future
rsc.li/greenchem
Accepted Manuscripts are published online shortly after acceptance,
before technical editing, formatting and proof reading. Using this free
service, authors can make their results available to the community, in
citable form, before we publish the edited article. We will replace this
Accepted Manuscript with the edited and formatted Advance Article as
soon as it is available.
You can find more information about Accepted Manuscripts in the
Information for Authors.
Please note that technical editing may introduce minor changes to the
text and/or graphics, which may alter content. The journal’s standard
Terms & Conditions and the Ethical guidelines still apply. In no event
shall the Royal Society of Chemistry be held responsible for any errors
or omissions in this Accepted Manuscript or any consequences arising
from the use of any information it contains.
ISSN 1463-9262
PAPER
Paul T. Anastas et al.
The Green ChemisTREE: 20 years after taking root with the 12
principles
rsc.li/greenchem

Please do not adjust margins
Page 1 of 5
Green Chemistry
View Article Online
DOI: 10.1039/C9GC01802F
COMMUNICATION
Cascade bio-hydroxylation and dehalogenation for one-pot
enantioselective synthesis of optically active -halohydrins from
halohydrocarbons
Received 00th January 20xx,
Accepted 00th January 20xx
Hai-Bo Cui,a,† Ling-Zhi Xie,a,† Nan-Wei Wan,a Qing He,a Zhi Li,b and Yong-Zheng Chen*,a
DOI: 10.1039/x0xx00000x
Stereoselective
hydroxylation
and
enantioselective enantioenriched -halohydrins due to their high selectivity,
dehalogenation cascade reaction was developed for the synthesis mild reaction conditions and environmental compatibility.9
of optically active -haloalcohols from halohydrocarbons. This Until now, four biocatalytic methods have been reported to
cascade system employed P450 and halohydrin dehalogenase as prepare enantioenriched -halohydrins that are summarized as
two compatible biocatalysts, allowing a straightforward, greener follows: (I) carbonyl reductases (KREDs)10 and (II) alcohol
and efficient access to -halohydrins with excellent dehydrogenases (ADHs)11 catalyzed asymmetric reduction of
enantioselectivities (98-99%).
prochiral haloketones; (III) lipases12 and (IV) halohydrin
dehalogenases (HHDHs)13 catalyzed kinetic solution of racemic
halohydrins. Some of these methods have been exploited and
applied to synthesize halohydrins with excellent yield,
enantiomeric excesses (ee) and a broad substrate scope.14
However, it should be noted that all these methods mentioned
above absolutely require prior oxygen-functionalization at the
target C-H bonds to form the carbonyl or hydroxyl group
substituted precursors (Fig. 1).
It is well known that enantiopure -halohydrins are
particularly interesting as synthons for the preparation of a
large number of bioactive products including natural products,
agrochemicals and pharmaceuticals.1 Optically active 2-chloro-
1-phenylethanol, for instance, is the key precursor for the
synthesis of anti-depressants α- or -adrenergic drugs such as
Tomoxetine, Fluoxetine and Nisoxetine.2 They also can be easily
converted to the corresponding chiral epoxides with controlled
stereochemistry,3 which opens a large spectrum for further
synthetic applications. In addition, growing methods have been
developed for the transformations of enantiopure halohydrins
into a broad range of functional groups to construct various
useful chiral organic compounds, including aminoalcohols,4
azidoalcohols,5 hydroxynitriles,6 and 1, 2-diols,7 which provides
a powerful strategy for asymmetric synthesis.
Previous work: Using Oxygen-Functionalized Substrates
OH
O
X
X
(I) KREDs
(II) ADHs
Asymmetric Reduction
X
X
X
*
R
R
R
OH
OAc
*
OH
OH
X
Asymmetric
Kinetic Resolution
(III) Lipases
O
*
R
R
+
R
O
OH
O
(IV) HHDHs
X
Asymmetric
Kinetic Resolution
*
*
Even though some methods access to enantiopure -
halohydrins have been developed, especially via transition
metal catalyzed asymmetric transfer hydrogenation of the
+
R
R
H+, X-
This work: Using Oxygen as Oxidant
OH
corresponding -halo-ketones,3b, it is still a challenge to
8
OH
OH
O
X
X
X
X
P450PL2-4
HheA10
synthesize these enantiopure -halohydrins with more greener
and atom economic strategies. In the past decades, many
biocatalytic routes have been emerged to synthesize the
R
R
R
R
+
R
+
O2
major
minor
minor
major
73%-90% ee
98-99%
ee
X=Cl or Br
One-Pot Cascade Reaction System Combining Asymmetric Hydroxylation and Enantioselective Dehalogenation
Fig. 1 Biocatalytic approaches to enantiopure -halohydrins.
a. Key Laboratory of Biocatalysis & Chiral Drug Synthesis of Guizhou Province, Green
Pharmaceuticals Engineering Research Center of Guizhou Province, School of
Pharmacy, Zunyi Medical University, Zunyi, 563000, China
Cytochrome P450 monooxygenases (P450s) are the most
versatile enzymes and capable of catalyzing a wide range of
synthetically challenging oxidation reactions such as
hydroxylation,15 sulfoxidation,16 and C-H amination.17 P450s are
able to introduce an oxygen atom into a C-H bond under normal
pressure and room temperature. We therefore were interested
b. Department of Chemical and Biomolecular Engineering, National University of
Singapore, 4 Engineering Drive 4, Singapore 117585, Singapore
* E-mail: yzchen@zmu.edu.cn
† These authors contributed equally to this work.
Electronic Supplementary Information (ESI) available: [details of any supplementary
information available should be included here]. See DOI: 10.1039/x0xx00000x
Please do not adjust margins

Please do not adjust margins
Green Chemistry
Page 2 of 5
COMMUNICATION
Journal Name
Table 1. Screening of P450 strains for asymmetric hydroxylation
of 1a.
in the synthesis of enantiopure -halohydrins through P450-
catalyzed direct asymmetric hydroxylation of prochiral
halohydrocarbons. Herein, enantioenriched -halohydrins 2a-
View Article Online
DOI: 10.1039/C9GC01802F
H
OH
Cl
Cl
2m
were
synthesized
from
the
corresponding
E. coli cells (P450x)
pH 8.0, 30 oC, 24 h
*
halohydrocarbons 1a-1m through P450PL2-4 catalyzed
asymmetric hydroxylation. In addition, the ee values were
improved up to 98-99% by developing a one-pot cascade
biocatalysis using P450PL2-4 and halohydrin dehalogenase
HheA10 (Fig. 1).
1a
2a
(R) or (S)-
Entrya
1
2
3
4
5
6
7
8
Biocatalyst
P450PL2-1
P450PL2-2
P450PL2-3
P450PL2-4
P450PL2-5
P450PL7-1
P450PL7-2
P450PL7-3
P450PL7-4
P450PL7-5
Yield 2a (%)b
ee 2a (%)b
75
76
77
77
77
77
76
76
76
76
n.d.
35
90
Conf.c
48
26
33
49
20
48
32
33
49
17
R
R
R
R
R
R
R
R
R
R
n.d.
S
Previously, we have expressed several P450s from strain
Parvibaculum lavamentivorans DS-1 and constructed a series of
recombinant Escherichia coli strains harboring P450 enzyme
and redox partner Fdx-Fdr (ferredoxin-ferredoxin reductase).18
Additionally, we have obtained another thirteen E. coli strains
containing P450pyr mutants and the corresponding Fdx-Fdr
from professor Li group.19 With these P450 biocatalysts in hand
(Table S1), we initially examined their catalytic activity and
stereoselectivity using 2-chloroethyl)benzene (1a) as a model
substrate. Biocatalytic reactions were carried out using
recombinant E. coli cells as catalyst without addition of any
exogenous cofactor. After incubation at 30 oC for 24 h, the yield
and ee of the product 2-chloro-1-phenlyehthanol (2a) were
determined using chiral HPLC (Table 1). The result indicated that
all the E. coli strains containing P450PL2 or P450PL7 exhibited
hydroxylation activity and R stereoselectivity to 1a, which
produced 2a in 17-49% yields and up to 76% ee (Table 1, entries
1-10). According to our previous study of sulfoxidation reactions,
hydroxylation activity of these P450 strains was also dependent
on the redox partner.18 For the same P450, the Fdx2-Fdr or
Fdx4-Fdr redox partner gave the relative higher yields than
other redox partners (Table S1-S2). Surprisingly, most of
P450pyr mutants could not convert 1a to 2a, except for
P450pyr-M4, P450pyr-M6 and P450pyr-M9 (Table 1, entries 12-
14). These three P450pyr variants showed the opposite
stereoselectivity to P450PL strains, which produced (S)-2a with
the ee value up to 90%. However, their yields were much lower
than that of P450PL strains. As we known, P450pyr is able to
catalyze terminal-selective hydroxylation of non-activated C-H
bonds and has been successfully engineered for the subterminal
hydroxylation of alkanes with excellent regio- and
enantioselectivity.15a,20 Herein, we tested thirteen P450pyr
mutants containing 1-6 mutations and found three variants
could convert 1a to 2a, catalyzing the hydroxylation of activated
C-H bond at subterminal position. Interestingly, the best active
mutant E. coli P450pyr-M4 (N100S/F430I) for subterminal
hydroxylation of propylbenzene almost lost hydroxylation
activity,15a because the yield was not detectable under normal
reaction conditions (Table 1, entry 11). The F430I mutation also
existed in the best enantioselective P450pyr-M6, and its role in
stereocontrol of S-selective hydroxylation of propylbenzene has
been explained by molecular dynamics and docking
simulation.15a What needs to be emphasized is that all the E. coli
strains in the absence of P450 and Fdx-Fdr genes were also
carried out as controls, and no hydroxylation activity was
observed (Table S2, entries 24-27).
9
10
11
12
13
14
P450pyr-M2 n.d.
P450pyr-M4 trace
P450pyr-M6 17
S
S
P450pyr-M9
8
57
a
Reactions were carried out in 5 mL PBS buffer (50 mM, pH 8.0)
containing 2 mM of substrate 1a and 10 g cdw/L of recombinant E. coli
cells. b Yield and ee were measured by chiral HPLC analysis after reaction
for 24 h, see Table S2 for details. c Absolute configuration was confirmed
using commercial (R)-2a and (R,S)-2a as references. n.d. = not detected.
Subsequently, the strains P450PL2-4 and P450pyr-M6 were
selected for the optimization of reaction conditions. Though the
P450pyr-M6 exhibited excellent S enantioselectivity toward 1a
(entry 11, Table 1), its catalytic activity was really low which
gave only 37% yield of 2a after reaction optimization (data not
shown). Herein, we only discussed the optimization results of
strain P450PL2-4 (Fig. 2). The results in Fig. 2A indicated that the
yield was dramatically influenced by the cell density. Increasing
cell density from 5 to 30 g cdw/L improved the yield, while
further increasing cell density to 50 g cdw/L by no means
obtained a higher yield. The highest yield was found at pH 8.5,
which was illustrated by Fig. 2B. In addition, both the yield and
ee were influenced by reaction temperature (Fig. 2C). The
o
highest ee was found at 20 C, while the corresponding yield
o
was only 40% of that obtained at 35 C. With the increase of
temperature from 35 to 50 oC, the ee slowly reduced to 73% and
the yield significantly decreased to 16%. To sum up, the reaction
o
conditions were set at pH 8.5 and 35 C using 30 g cdw/L of
recombinant E. coli cells.
2 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 3 of 5
Green Chemistry
Please do not adjust margins
Journal Name
COMMUNICATION
chlorohydrins with either substituted or non-substituted group
View Article Online
120
yield of 2a (%)
ee of (R)-2a (%)
were generally higher than that ofDOtI:h1e0.10c3o9r/rCe9sGpCo0n1d80in2gF
bromohydrins. These results might be caused from that the
higher electronegativity of chloro group leading the benzylic C-
H bond easier to accept oxygen. A decrease in activity was also
observed in the wake of decrease in electron-withdrawing
capability of substituent on phenyl (Table 2, entry 5 vs 6). Most
chlorohydrins exhibited the similar ee values to the
corresponding bromohydrins. It was worth noting that almost
all the tested halohydrocarbons yielded the corresponding R
halohydrins with 80-90% ee, and only 2d and 2k showed >90%
ee.
100
80
60
40
20
0
5
20
10
30
50
9.0
50
(A)
Cell density (g cdw/L)
120
100
80
yield of 2a (%)
ee of (R)-2a (%)
Table 2. Asymmetric hydroxylation of pro-chiral
halohydrocarbons 1a-1m using E. coli (P450PL2-4) cells.
H
OH
60
X
X
E. coli (P450PL2-4 )
R
R
pH 8.5, 35 oC, 12 h
40
1a-1m
2a-2m
20
Yield 2 ee (R)-2
0
Entrya
R
X
Subs. Prod.
7.0
8.0
8.5
7.5
(%)b
80
(%)b
82
(B)
pH value
1
2
3
4
5
6
7
8
H
o-CH3
m-CH3 Cl 1c
p-CH3
p-F
m-Br
H
o-CH3
Cl 1a
Cl 1b
2a
2b
2c
2d
2e
2f
2g
2h
2i
trace
80
n.d.
85
120
100
80
yield of 2a (%)
ee of (R)-2a (%)
Cl 1d
Cl 1e
Cl 1f
Br 1g
Br 1h
10
99
81
87
29
84
60
75
82
40
trace
35
n.d.
90
20
9
m-CH3 Br 1i
10
11
12
13
p-CH3
p-F
p-Cl
Br 1j
Br 1k
Br 1l
Br 1m
2j
2k
2l
36
26
22
16
80
95
80
88
0
20
30
40
Temperature (oC)
35
45
(C)
m-Br
2m
Fig. 2 Conditions optimization for the E. coli (P450PL2-4)
catalyzed asymmetric hydroxylation of 1a: cell density (A);
reaction pH (B); reaction temperature (C). (see Table S3-S5 for
details).
a All the reactions were performed in 5 mL PBS buffer (50 mM, pH 8.5)
containing 2 mM of substrate 1a-1m and 30 g cdw/L of E. coli (P450PL2-
b
4) cells; The yield and ee of halohydrins were determined by chiral
HPLC analysis after incubation at 35 oC for 12 h. Subs.=substrate;
Prod.=product; n.d.= not detected.
Under the optimized conditions, the substrate scope was
investigated
with
various
chlorohydrocarbons
and
Recent years, biocatalytic cascades have been rapidly
developed and lead to the generation of complex valuable
chemicals from simple precursors.24 The P450s have also been
used to develop cascade reactions for multiple
biotransformation reactions.25 Recently, we have expressed
and characterized a novel HHDH (HheA10) from Tsukamurella
sp. 1534, which exhibited high S enantioselectivity toward -
halohydrins.26 Inspired by the combination of sequential
biocatalytic reactions, we attempted to improve the ee of
halohydrins 2a-2m by consumption of the S isomer halohydrins
with the HheA10. With this idea in mind, a “one-pot”
biocatalytic cascade reaction was constructed using P450PL2-4
and HheA10 (Fig. 3). In the first step, halohydrocarbon was
catalyzed by P450PL2-4 to generate major R and minor S
halohydrin with moderate ee (R isomer). Subsequently, the
bromohydrocarbons. As shown in Table 2, substrates with
diverse ortho-, meta-, and para-substituted group on phenyl
ring, such as F, Cl, Br and methyl, were found to be suitable for
the biotransformation, generating -halohydrin products in 16-
81% yields with moderate ee. Among ortho-, meta-, and para-
substituted
halohydrocarbons,
the
ortho-substituted
derivatives were not suitable substrates for hydroxylation by
P450PL2-4 (entry 2 and 8) and gave very low yields (<5%). These
results revealed that the steric size of the ortho-substituted
group had great effect on the activity, which was also in
agreement with the report results of P450 BM321 and P450tol
for benzylic hydroxylation of aromatic hydrocarbons.22 The
substitution at the ortho-position might have steric effect on
the oxygen attack from the ferryl species (cytochrome P450
Compound I),23 and reduces oxidation activation efficiency at
the benzylic C-H bond. Interestingly, the yields of most
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 3
Please do not adjust margins

Please do not adjust margins
Green Chemistry
Page 4 of 5
COMMUNICATION
Journal Name
99
HheA10 converted the minor S halohydrin into S epoxide. As a
result, the ee of R halohydrin increased to a higher value.
11
12
13
p-F
p-Cl
m-Br
Br 1k
Br 1l
Br 1m
2k
2l
2m
28
23
24
View Article Online
DOI: 10.1039/C9GC01802F
99
99
OH
OH
a All the reactions were performed in 5 mL PBS buffer (50 mM, pH 8.5)
containing 2 mM of substrate 1a-1m and 30 g cdw/L of E. coli cells
(P450PL2-4). After reaction at 35 oC for 8 h, 2 mL cell-free extract of
HheA10 were added, proceeding for another 3 h (1a-1f) or 1 h (1g-1m).
X
X
R
R
H
R
Major
R
Major
X
P450PL2-4
HheA10
R
OH
O
b
The yield and ee values were determined by chiral HPLC analysis.
X
X=Cl or Br
R
R
Subs.=substrate; Prod.=product; n.d.= not detected.
S
Minor
S
Minor
In summary, we developed a direct and greener route for
the synthesis of enantioenriched -halohydrins via P450PL2-4-
catalyzed asymmetric hydroxylation of halohydrocarbons at
benzylic C-H bonds. In addition, a hydroxylation-dehalogenation
enzymatic cascade reaction was constructed by using the
P450PL2-4 and HheA10, which produced -halohydrins products
in excellent ee. This synthetic method uses oxygen as an oxidant,
avoids the use of oxygen-functionalized substrates, and
achieves the excellent product ee by a biocatalytic process in
“one-pot”.
Moderate ee
High ee
Fig. 3 The hydroxylation-dehalogenation cascade process for
one-pot enantioselective synthesis of chiral -haloalcohols.
To avoid the excessive dehalogenation of R halohydrin in the
second step, the cell-free extract of HheA10 was added after
hydroxylation for 8 h by E. coli cells (P450PL2-4). As we have
known, HHDH was more active to bromohalohydrin than
chlorohalohydrin. Consequently, the dehalogenation reaction
times in the cascade process for bromohydrocarbons and
chlorohalohydrins were 1 h and 4 h, respectively. The yield and
ee of -halohydrin products 2a-2m were determined and
showed in Table 3 (except 2b and 2h with low activity). As we
expected, the increase of ee was observed for the halohydrins
product (such as entry 1, Table 3 vs entry 1, Table 2), and all the
tested halohydrins were generated in >98% ee. The yields of
some halohydrins reduced slightly, which might result from the
conversion of S isomer and the excessive conversion of R isomer
in the dehalogenation process. In general, the optical purity of
-halohydrins could be improved by using the hydroxylation-
dehalogenation cascade strategy in a short time. This strategy
might be more effective than obtaining a stereoselectivity-
improved P450 variant via a complicated and time-consuming
engineering process, especially for the asymmetric
hydroxylation reaction. More importantly, P450-catalyzed C-H
direct hydroxylation process shows greener access, which do
not need the preoxidation treatment at the target C-H bond.
Conflicts of interest
There are no conflicts to declare.
Acknowledgements
We are grateful for financial support from the National Natural
Science Foundation of China (No. 21562054 and 21662050),
Guizhou Science and Technology Department (QKHRC-2016-
4029, QKHPTRC-2016-5801, QKHJC-2019-1467 and QKHZC-
2019-2579), Program for Outstanding Youth of Zunyi Medical
University (17zy-001), National First-Rate Construction
Discipline of Guizhou Province (Pharmacy) (YLXKJS-YX-04) and
the Fifth Batch of Talent Base in Guizhou Province (2016).
Notes and references
Table 3. Synthesis of optically active -halohydrins 2 via one-pot
cascade biocatalysis.
1
H. Hamada, T. Miura, H. Kumobayashi, T. Matsuda, T. Harada
and K. Nakamura, Biotechnol. Lett., 2001, 23, 1603; (b) S. Eirik,
H. Jarle, V. Anders and A. Thorleif, Eur. J. Org. Chem., 2004,
2004, 1239; (c) J. Y. L. Chung, R. Cvetovich, J. Amato, J. C.
McWilliams, R. Reamer and L. DiMichele, J. Org. Chem., 2005,
70, 3592; (d) M. C. Bryan, D. J. Burdick, B. K. Chan, Y. Chen, S.
Clausen, J. Dotson, C. Eigenbrot, R. Elliott, E. J. Hanan, R.
Heald, P. Jackson, H. La, M. Lainchbury, S. Malek, S. E. Mann,
H. E. Purkey, G. Schaefer, S. Schmidt, E. Seward, S. Sideris, S.
Wang, I. Yen, C. Yu and T. P. Heffron, ACS Med. Chem. Lett.,
2016, 7, 100. (e) T. d. Fonseca, L. D. Lima, M. d. de Oliveira, T.
L. de Lemos, D. Zampieri, F. Molinari and M. C. de Mattos,
Eur. J. Org. Chem., 2018, 2018, 2110.
D. Zhu, C. Mukherjee and L. Hua, Tetrahedron: Asymmetry,
2005, 16, 3275.
(a) P. Besse, T. Sokoltchik and H. Veschambre, Tetrahedron:
Asymmetry, 1998, 9, 4441; (b) T. Hamada, T. Torii, K. Izawa, R.
Noyori and T. Ikariya, Org. Lett., 2002, 4, 4373; (c) R. Imashiro
and M. Seki, J. Org. Chem., 2004, 69, 4216; (d) T. Poessl, B.
Kosjek, U. Ellmer, C. Gruber, K. Edegger, K. Faber, P.
OH
H
E. coli cells (P450PL2-4
Cell-free extract (HheA10)
)
X
X
R
R
pH 8.5, 35 o
C
2a-2m
1a-1m
Yield
(%)b
85
n.d.
45
5
62
41
46
2
ee (R)-
2 (%)b
98
n.d.
99
99
99
99
99
Entrya
R
X
Subs. Prod.
1
2
H
o-CH3
Cl 1a
Cl 1b
2a
2b
2c
2d
2e
2f
2g
2h
2i
3
m-CH3 Cl 1c
4
5
6
7
p-CH3
p-F
m-Br
H
Cl 1d
Cl 1e
Cl 1f
Br 1g
Br 1h
2
3
8
o-CH3
n.d.
31
12
n.d.
99
98
9
10
m-CH3 Br 1i
p-CH3 Br 1g
2g
4 | J. Name., 2012, 00, 1-3
This journal is © The Royal Society of Chemistry 20xx
Please do not adjust margins

Page 5 of 5
Green Chemistry
Please do not adjust margins
Journal Name
COMMUNICATION
Hildebrandt, U. Bornscheuer and W. Kroutil, Adv. Synth.
Catal., 2005, 347, 1827; (e) K. Wu, H. Wang, L. Chen, H. Fan,
Z. Zhao and D. Wei, Appl. Microbiol. Biot., 2016, 100, 8757.
(a) S. P. Hameed, M. Chinnapattu, G. Shanbag, P. Manjrekar,
K. Koushik, A. Raichurkar, V. Patil, S. Jatheendranath, S. S.
Rudrapatna, S. P. Barde, N. Rautela, D. Awasthy, S. Morayya,
C. Narayan, S. Kavanagh, R. Saralaya, S. Bharath, P. Viswanath,
Y.-J Zhang, J.-H. Xu and H.-L. Yu, Adv. Synth. Catal., 2017, 359,
View Article Online
426.
DOI: 10.1039/C9GC01802F
15 (a) Y. Yang, J. Liu and Z. Li, Angew. Chem. Int. Ed., 2014, 53,
3120; (b) S. Kille, F. E. Zilly, J. P. Acevedo and M. T. Reetz, Nat.
Chem., 2011, 3, 738; (c) E. Weber, A. Seifert, M. Antonovici, C.
Geinitz, J. Pleiss and V. B. Urlacher, Chem. Commun., 2011, 47,
944.
4
K. Mukherjee, B. Bandodkar, A. Srivastava, Panduga, V. J. 16 (a) P. Gao, A. Li, H. H. Lee, D. I. C. Wang and Z. Li, ACS Catal.,
Reddy, K. R. Prabhakar, A. Sinha, B. Jiménez-Díaz, M. M. S.
Martínez, I. Angulo-Barturen, S. Ferrer, L. M. Sanz, F. J. Gamo,
2014, 4, 3763; (b) J.-D. Zhang, A.-T. Li, Y. Yang and J.-H. Xu,
Appl. Microbiol. Biot., 2010, 85, 615.
S. Duffy, V. M. Avery, P. A. Magistrado, A. K. Lukens, D. F. 17 (a) C. K. Prier, R. K. Zhang, A. R. Buller, S. Brinkmann-Chen and
Wirth, D. Waterson, V. Balasubramanian, P. S. Iyer, S.
Narayanan, V. Hosagrahara, V. K. Sambandamurthy and S.
Ramachandran, J. Med.Chem. 2014, 57, 5702; (b) A. Murugan,
V. K. Kadambar, S. Bachu, M. R. Reddy, V. Torlikonda, S. G.
Manjunatha, S. Ramasubramanian, S. Nambiar, G. P. Howell
and J. Withnall, Tetrahedron Lett., 2012, 53, 5739.
(a) T. Ohkuma, K. Tsutsumi, N. Utsumi, N. Arai, R. Noyori and 18 K. Wu, L. Tang, H. Cui, N. Wan, Z. Liu, Z. Wang, S. Zhang, B. Cui,
K. Murata, Org. Lett., 2007, 9, 255; (b) L. S. Campbell-Verduyn, W. Han and Y. Chen, ChemCatChem, 2018, 10, 5410.
W. Szymański, C. P. Postema, R. A. Dierckx, P. H. Elsinga, D. B. 19 J. B. van Beilen, E. G. Funhoff, A. van Loon, A. Just, L. Kaysser,
F. H. Arnold, Nat. Chem., 2017, 9, 629; (b) T. K. Hyster, C. C.
Farwell, A. R. Buller, J. A. McIntosh and F. H. Arnold, J. Am.
Chem. Soc., 2014, 136, 15505; (c) A. McIntosh, J. P. S. Coelho,
C. C. Farwell, Z. J. Wang, J. C. Lewis, T. R. Brown and F. H.
Arnold, Angew. Chem. Int. Ed., 2013, 52, 9309; (d) R. Singh, M.
Bordeaux and R. Fasan, ACS Catal., 2014, 4, 546.
5
6
Janssen and B. L. Feringa, Chem. Commun., 2010, 46, 898.
(a) I. Kévin, S. Jérémie, R. Pascal, B. Jean-François and M.
Angela, Eur. J. Org. Chem., 2014, 2014, 4099; (b) S. Jérémy, I. 20 W. Zhang, W. L. Tang and Z. Li, Adv. Synth. Catal., 2010, 352,
M. Bouza, R. Holtackers, M. Röthlisberger, Z. Li and B. Witholt,
Appl. Environ. Microb., 2006, 72, 59.
Kévin, P. Julien, F. Gilles, R. Pascal, V. Arnaud, B. Jean-François
and M. Angela, Adv. Synth. Catal., 2013, 355, 3613.
J. Barluenga, J. Flórez and M. Yus, J. Chem. Soc., Chem.
Commun., 1982, 0, 1153.
3380.
21 K. Neufeld, J. Marienhagen, U. Schwaneberg and J. Pietruszka,
Green Chem., 2013, 15, 2408.
7
8
22 A. Li, S. Wu, J. P. Adams, R. Snajdrova and Z. Li, Chem.
Commun., 2014, 50, 8771.
(a) C. Yin, W. Wu, Y. Hu, X. Tan, C. You, Y. Liu, Z. Chen, X.-Q.
Dong, X. Zhang, Adv. Synth. Catal., 2018, 360, 2119; (b) T. 23 J. Rittle and M. T. Green, Science, 2010, 330, 933.
Touge, T. Hakamata, H. Nara, T. Kobayashi, N. Sayo, T. Saito, 24 (a) S. P. France, L. J. Hepworth, N. J. Turner and S. L. Flitsch,
Y. Kayaki and I. Takao, J. Am. Chem. Soc., 2011, 133, 14960; (c)
Y. Yamato, T. Taichiro, N. Hideki, M. Kazuhiko, F. Mitsuhiko, K.
Yoshihito and I. Takao, Adv. Synth. Catal., 2018, 360, 568.
ACS Catal., 2017, 7, 710; (b) J. H. Schrittwieser, S. Velikogne,
M. Hall and W. Kroutil, Chem. Rev., 2018, 11, 270; (c) J. M.
Sperl, V. Sieber, ACS Catal., 2018, 8, 2385.
9
(a) A. Schmid, J. S. Dordick, B. Hauer, A. Kiener, M. Wubbolts 25 (a) R. Agudo and M. T. Reetz, Chem. Commun., 2013, 49,
and B. Witholt, Nature, 2001, 409, 258; (b) J. Tao and J.-H. Xu,
Curr. Opin. Chem. Biol., 2009, 13, 43; (c) R. A. Sheldon and J.
M. Woodley, Chem. Rev., 2018, 118, 801; (d) Z.-M. Wu, R.-C.
Zheng, X.-L. Tang and Y.-G. Zheng, App. Microbiol. Biot. 2017,
101, 1953.
10914; (b) A. Li, A. Ilie, Z. Sun, R. Lonsdale, J.-H. Xu and M. T.
Reetz, Angew. Chem. Int. Edit., 2016, 55, 12026; (c) M.
Tavanti, F. Parmeggiani, J. R. G. Castellanos, A. Mattevi and N.
J. Turner, ChemCatChem, 2017, 9, 3338.
26 N. Wan, J. Tian, H. Wang, M. Tian, Q. He, R. Ma, B. Cui, W. Han
and Y. Chen, Bioorg. Chem., 2018, 81, 529.
10 (a) Y. Xie, J.-H. Xu and Y. Xu, Bioresource Technol., 2010, 101,
1054; (b) Y. Xie, J.-H. Xu, W.-Y. Lu and G.-Q. Lin, Bioresource
Technol., 2009, 100, 2463; (c) S.-Y. Chen, C.-X. Yang, J.-P Wu,
G. Xu and L.-R. Yang, Adv. Synth. Catal., 2013, 355, 3179; (d)
F. Qin, B. Qin, T. Mori, Y. Wang, L. Meng, X. Zhang, X. Jia, I. Abe
and S. You, ACS Catal., 2016, 6, 6135; (e) X. Chen, H. Zhang, J.
Feng, Q. Wu and D. Zhu, ACS Catal., 2018, 8, 3525.
11 (a) N. Itoh, K. Isotani, M. Nakamura, K. Inoue, Y. Isogai and Y.
Makino, Appl. Microbiol. Biot., 2012, 93, 1075; (b) J. Mangas-
Sánchez, E. Busto, V. Gotor-Fernández, F. Malpartida and V.
Gotor, J. Org. Chem., 2011, 76, 2115; (c) D. Zhu, B. A. Hyatt
and L. Hua, J. Mol. Catal. B-Enzym., 2009, 56, 272.
12 (a) I. M. Ferreira, R. H. V. Nishimura, A. B. A. Souza, G. C.
Clososki, S. A. Yoshioka and A. L. M. Porto, Tetrahedron Lett.,
2014, 55, 5062; (b) A. Träff, K. Bogár, M. Warner and J.-E.
Bäckvall, Org. Lett., 2008, 10, 4807; (c) O. Pàmies and J.-E.
Bäckvall, J. Org. Chem., 2002, 67, 9006.
13 (a) M. Majerić Elenkov, L. Tang, B. Hauer and D. B. Janssen,
Org. Lett., 2006, 8, 4227; (b) R. M. Haak, C. Tarabiono, D. B.
Janssen, A. J. Minnaard, J. G. de Vries and B. L. Feringa, Org.
Biomol. Chem., 2007, 5, 318; (c) A. Westerbeek, J. G. E. van
Leeuwen, W. Szymanski, B. L. Feringa and D. B. Janssen,
Tetrahedron, 2012, 68, 7645; (d) H. Arabnejad, M. Dal Lago, P.
A. Jekel, R. J. Floor, A-M. W. H. Thunnissen, A. C. Terwisscha
van Scheltinga, H. J. Wijma and D. B. Janssen, Protein Eng. Des.
Sel., 2017, 30, 175.
14 (a) W. Borzęcka, I. Lavandera and V. Gotor, J. Org. Chem.,
2013, 78, 7312; (b) G.-C. Xu, H.-L. Yu, X.-Y. Zhang and J.-H. Xu,
ACS Catal., 2012, 2, 2566; (c) Y.-P. Shang, Q. Chen, X.-D. Kong,
This journal is © The Royal Society of Chemistry 20xx
J. Name., 2013, 00, 1-3 | 5
Please do not adjust margins