One-pot hydroacetylation of menadione (vitamin K3) to menadiol diacetate (vitamin K4) by heterogeneous catalysis

Article abstract of DOI:10.1002/adsc.201100718

Vitamin K₄ (menadiol diacetate, MDD) can be easily synthesized through cleaner and more efficient catalytic alternatives following the green chemistry principles. Ionic gold-based hydroxylated fluorides are active bi-functional catalysts for the one-pot hydroacetylation of menadione leading to MDD with 77% selectivity. Unprecedent results were obtained in the presence of oxide-fluoride catalysts by using a microwave-assisted hydrogen-transfer (Meerwein-Ponndorf-Verley reaction) coupled with an acetylation approach, yielding very high selectivities for the target product (95%). Copyright

Full text of DOI:10.1002/adsc.201100718

COMMUNICATIONS
DOI: 10.1002/adsc.201100718
One-Pot Hydroacetylation of Menadione (Vitamin K ) to
3
Menadiol Diacetate (Vitamin K ) by Heterogeneous Catalysis
4
a
a
a
b
Claudiu Dobrinescu, Elena E. Iorgulescu, Constantin Mihailciuc, Dan Macovei,
c
d,
a,
Stefan Wuttke, Erhard Kemnitz, * Vasile I. Parvulescu, *
and Simona M. Coman *
a,
a
Faculty of Chemistry, University of Bucharest, Bdul Regina Elisabeta, 4–12, Bucharest 030016, Romania
Fax : (+40)-21-410-0241; phone: (+40)-21-410-0241; e-mail: vasile.parvulescu@g.unibuc.ro or simona.coman@g.unibuc.ro
National Institute of Materials Physics, Atomistilor Str. 105bis, PO Box MG. 7, Magurele-Bucharest 077125, Romania
University of Munich (LMU), Department of Chemistry, Butenandstr. 5–13 (E), 81377 Munich, Germany
Humboldt-Universitꢀt zu Berlin, Institut fꢁr Chemie, Brook-Taylor-Straße 2, 12489 Berlin, Germany
b
c
d
Fax : (+49)-30-2093-7468; e-mail: erhard.kemnitz@chemie.hu-berlin.de or erhard.kemnitz@chemie.hu-berlin.de
Received: September 15, 2012; Revised: February 1, 2012; Published online: April 24, 2012
Supporting information for this article is available on the WWW under http://dx.doi.org/10.1002/adsc.201100718.
[
1]
Abstract: Vitamin K (menadiol diacetate, MDD)
blood clotting. Among all forms of vitamin K, vita-
4
can be easily synthesized through cleaner and more
efficient catalytic alternatives following the green
chemistry principles. Ionic gold-based hydroxylated
fluorides are active bi-functional catalysts for the
one-pot hydroacetylation of menadione leading to
MDD with 77% selectivity. Unprecedent results
were obtained in the presence of oxide-fluoride cat-
alysts by using a microwave-assisted hydrogen-
transfer (Meerwein–Ponndorf–Verley reaction) cou-
pled with an acetylation approach, yielding very
high selectivities for the target product (95%).
min K (menadiol diacetate, MDD) is the most stable
4
and thus easiest to store. Owing to these qualities, it
is a significant candidate as a synthetic substitute for
natural vitamins K although its biological activity is
[
2]
2–3 times lower. The conventional synthesis of
MDD consists of three separate consecutive steps: re-
duction of menadione (1) to menadiol (2) (Scheme 1,
path A), monoacetylation of menadiol (2) to mena-
diol monoacetate (3) (Scheme 1, path B) and mono-
AHCTUNGTRENNUGNa cetylation of menadiol monoacetate (3) to menadiol
diacetate (MDD, 4) (Scheme 1, path C).
Unfortunately, as in many other cases from the fine
chemicals and pharmaceuticals sector the synthesis of
these compounds is still based on stoichiometric reac-
tions in the field of organic chemistry where often
large amounts of waste are formed, even though
cleaner alternatives have been reported. Therefore,
the reduction of menadione (1) to menadiol (2)
Keywords: hydroxylated fluorides; ionic gold cata-
lyst; microwaves; oxide-fluorides; vitamin k4
The term “vitamin K” is used as the generic name for (Scheme 1, path A) is still preferably employed by
2
-methyl-1,4-naphthoquinone as well as for all deriva- using inorganic reduction reagents such as sodium di-
[3–5] [6]
tives that qualitatively exhibit the same biological ac- thionite (Na S O )
or Zn-ZnCl -EtOH reagent
2
2
2
4
tivity as phylloquinone (vitamin K ) in the control of while reports upon the catalytic hydrogenation of me-
1
[7,8]
nadione (1) are scarce and not sufficiently detailed.
On the other hand, menadiol diacetate (4) is usually
synthesized by using acetic anhydride, in the presence
of triethylamine and 4-(dimethylamino)pyridine
[
4]
(
DMAP). Such methodologies can not only gener-
ate high amounts of inorganic wastes but also raise
the price of MDD and decrease its output.
[9]
More recently, Raghavender Rao and co-workers
stated that menadiol triacetate may be obtained via
the Thiele–Winter reaction using bismuth(III) triflate
tive steps (paths A, B and C) versus direct hydroacetylation as a highly efficient catalyst. However, the use of ho-
path D).
AHCTUNGTRENNUNG
Scheme 1. The synthesis of MDD (4) by separate consecu-
(
Adv. Synth. Catal. 2012, 354, 1301 – 1306
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
1301

Claudiu Dobrinescu et al.
COMMUNICATIONS
mogeneous catalysts does not overcome the known Table 1. Catalytic performances of the nanoscopic partly hy-
droxylated fluorides in the acetylation of menadione or me-
nadiol to MDD 4.
disadvantages connected to the catalysts separation.
Increasingly stringent environmental legislation
from the last years has generated a pressing need for
cleaner methods of fine chemicals and pharmaceuti-
[10,11]
cals production.
One of the best solutions is the
substitution of classical stoichiometric methodologies
by cleaner heterogeneous catalytic alternatives.
Connected with this, Shmachkova and co-work-
[12]
ers
reported about an attractive one-pot catalytic
Catalyst
Xmenadione
%]
Xmenadiol
[%]
S2
[%]
S3
[%]
S4
[%]
hydroacetylation of menadione to MDD (Scheme 1,
path D) in the presence of a bifunctional Pd-based
catalyst in which Pd itself catalyzes the menadione
hydrogenation to menadiol and the carrier catalyzes
the acetylation reactions. Unfortunately, information
about the catalystꢃs nature (i.e., amount of palladium,
type of carrier, method of catalyst preparation) and
the reaction conditions are unavailable, the method
being in this case unusable.
[
[
a]
AlF -57
0
–
0
–
–
88.9
–
0
–
0
–
0
0.6
0
0
99.4
0
3
[
b]
AlF -57
3
[
[
a]
MgF -71
2
b]
MgF -71
84.4
0
>99.9
2
[
[
a]
b]
Menadione.
Menadiol.
Based on the great interest in cleaner catalytic syn-
theses of fine chemicals and pharmaceutical inter- >99.0%. Obviously, the acetylation of menadione re-
mediates, we took up the challenge task to find and quires a much stronger acidity, which may be provid-
[9]
develop a cleaner and efficient alternative for the syn- ed by catalysts like homogeneous bismuth triflate
thesis of MDD following some of the green chemistry and not by the nanoscopic acidic hydroxylated metal
[
15]
principles such as catalyst usage, replacement of fluorides – characterized by a medium acidity.
multi-steps synthesis with a one-pot methodology and Therefore, with the aim of a one-pot hydroacetyla-
use of alternative green activation methods for the re- tion alternative in mind we have focused on a bifunc-
actant molecules. Such conversions eliminate the re- tional catalyst (i.e., one exhibiting both hydrogenation
covery of intermediates and the presence of a catalyst and acidic functions). Taking into account that the
minimizes the need for stoichiometric amounts of re- nanoscopic acidic hydroxylated metal fluorides
agents, thereby reducing the waste generated.
Herein, we report the key results obtained in the menadiol to MDD, we prepared a series of bifunc-
proved to be highly efficient for the acetylation of
3+
one-pot synthesis of menadiol diacetate (MDD, vita- tional Au /MgF (or AlF ) catalysts using an easy
2
3
min K ) using three different kinds of heterogeneous and facile incipient wetness impregnation method fol-
4
[
16]
catalysts: (i) nanoscopic acidic hydroxylated metal lowing a reported procedure. Materials with 1 wt%
fluorides [MF (OH) , where M=Mg, Al; n=2, 3; and 4 wt% Au were obtained in this way. The catalyt-
x<0.1], (ii) ionic gold-based hydroxylated metal fluo- ic precursors were calcined at 100 and 1508C, respec-
rides [Au /MF (OH) ], and (iii) magnesium oxide tively. The obtained materials were denoted as
fluorides [Mg(O)(
nÀx
x
3+
nÀx
x
F ] as well as thermal and mi- AuxMg(Al)-y (x=wt%Au; y=calcination tempera-
nÀx)/2
x
crowave methods for activation of the reactants.
Nanoscopic acidic hydroxylated metal fluorides deposited on carriers with a very soft acidity such as
MF (OH) , in the following named MF for sim- SiO2.
ture). For comparison, the same active species were
[
nÀx
x
n
plicity], for which the acidic properties (Lewis/Brøn-
sted) can be easily tuned, have already demonstrated rides enabled, indeed, the one-pot hydroacetylation of
efficiency and versatility in the synthesis of other vita- menadione (1) (Scheme 1, path D) to diacetylated
Noteworthy, the deposition of gold on metal fluo-
ACHTUNGTRENNUNG
[
13,14]
mins (vitamin E, vitamin K and K -chromanol).
menadiol (4, MDD) while the deposition of gold on
1
1
They were further tested for the one-pot hydroacety- silica enabled only the hydrogenation of menadione
lation of menadione (1) to MDD (4) (Scheme 1, path (1) to menadiol (2) (Table 2, entries 1 and 2). The ob-
D) and the results are summarized in Table 1.
tained results, together with the results obtained in
As Table 1 shows, these materials (named as MgF2 the acylation of menadione/menadiol in the presence
and AlF ) are completely non-active for the one-pot of nanoscopic fluorides indicate that, as it was expect-
3
hydroacetylation of menadione to MDD (Scheme 1, ed, the one-pot synthesis of vitamin K needs a bifunc-
4
path D). In contrast, in the presence of the same hy- tional catalyst with a hydrogenation function for the
droxylated metal fluorides, the acetylation of mena- menadiol formation (Scheme 1, path A) and an acidic
diol (2) [obtained via the stoichiometric reduction of one for the acylation step (Scheme 1, paths B and C).
menadione (1)] occured with conversions (X%) of
Unfortunately, the rate of the menadiol acetylation
84–89% and selectivities (S%) to MDD (4) of (Scheme 1, paths B and C) is considerably slower in
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Adv. Synth. Catal. 2012, 354, 1301 – 1306

One-Pot Hydroacetylation of Menadione (Vitamin K ) to Menadiol Diacetate (Vitamin K )
3
4
Table 2. Catalytic performances of the gold-based catalysts
in the one-pot hydroacetylation of menadione 1 to MDD
Table 3. Peak currents and the cathodic peak current to
anodic peak current ratio for the investigated catalysts.
[
a]
4
.
Catalyst
First scan direction
positive Ipa [A] negative Ipc [A]
ÀI /I
pc pa
À6
À5
À6
À6
À5
À4
À5
À5
Au1Mg-100
Au4Mg-100
Au4Mg-150
Au4Al-100
5.169ꢅ10
1.119ꢅ10
6.849ꢅ10
3.674ꢅ10
À5.698ꢅ10
À2.621ꢅ10
À2.755ꢅ10
À7.669ꢅ10
11
23
4
20
Catalyst
Xmenadione [%] S2 [%] S3 [%] S4 [%]
and Au4Al-100 that are characterized by the highest
3+
loading of Au (Table 3, entries 2 and 4) led to con-
versions higher than 35% (Table 2, entries 6 and 8).
In contrast, the Au4Mg-150 sample with the lowest
Au1Si
Au4Si
Au1Mg-100
Au4Mg-100[
Au4Mg-100
10.8
32.6
11.7
37.2
57.1
71.3
> 99.9
1.6
99.5
99.3
8.7
11.5
10.8
9.7
0.5
0.7
0
0
0
2.5
21.7
43.1
77.0
0
91.3
86.0
67.5
47.2
14.5
>99.9
77.6
3+
loading of Au (Table 3, entry 3) is almost non active
Table 2, entry 8).
Furthermore, the Au species are quite rapidly
a]
b]
c]
(
[
Au4Mg-100[
3+
Au4Mg-100
Au4Mg-150
Au4Al-100
8.5
0
consumed in this reaction, which was further con-
firmed by cyclic voltammetry experiments (see the
Supporting Information). It is again very important to
note that a simple separation of the catalyst by filtra-
tion, followed by drying the catalyst in air at room
temperature for 24 h, led to an enhancement of the
conversion of menadione to menadiol up to a level of
33.6
12.0
10.4
[
[
[
a]
b]
c]
The second catalytic charge.
The third catalytic charge.
The fourth catalytic charge.
>
99.9% (Table 2, entries 5–7). Such a behavior is the
3+
comparison those with with pure hydroxylated metal result of restoring the Au
oxidation state by
fluorides and this can be assigned to the partial cover- a simple contact with air, as it has been confirmed
[
17]
age of its surface by gold. This behavior gives a clear previously by in situ XPS experiments.
However,
indication on the fact that, during the gold species im- the maximum selectivity to MDD (4) reached after
pregnation, part of the active sites for the menadiol four catalyst recycling was 77.0% (Table 2, entry 7).
acetylation are blocked. This effect is higher for
Au4Mg-100 than for Au4Al-100 (Table 2, entries 4 treatment temperature was also shown by the ꢄwhite
and 9). lineꢃ (WL) of the Au L -edge absorption spectra (see
The change of the chemical state of gold with the
3
Recently, we reported that several reactions includ- the Supporting Information). In addition, the XRD
ing the hydrogenation of isopulegol to menthol occur patterns show the formation of agglomerated gold
3+
[16]
preferentially on Au active species. The electro- particles for the Au4Mg-150 sample with preservation
chemical studies of the prepared fluorides-based cata- of the amorphous state of the pure nanoscopic fluo-
lysts provided evidence that gold exists in all samples ride (see the Supporting Information). Therefore, all
3
+
+
as both Au and Au species and that the ratios of used techniques display that upon increasing the
3+
these species depend on the catalyst composition and treatment temperature a decrease of the Au species
+
activation procedure (Table 3).
occurs due to the formation of Au or even metallic
3+
As Table 3 shows, the highest amount of Au was Au(0) species. This statement correlated well with the
3+
found for the Au4Mg-100 sample (Table 3, entry 2). catalytic results showing once again that Au are the
Changing the nature of the fluoride support from active sites for the hydrogenation of menadione to
MgF to AlF has less influence on the final composi- menadiol in the one-pot synthesis of MDD (4).
2
3
3+
tion of the catalysts, the amount of Au species being
Another envisagable solution for the one-pot syn-
almost unchanged (Table 3, entry 4). By increasing thesis of MDD (4) is the Meerwein–Ponndorf–Verley
the treatment temperature from 1008C to 1508C, (MPV) reduction (which until now has been less stud-
3+
+
[18–21]
a large fraction of Au becomes reduced to Au or ied in the field of heterogeneous catalysis)
cou-
even metallic species (Table 3, entries 2 and 3). Data pled with an acetylation reaction. This method could
compiled in Table 2 show that the conversion of me- have the advantage of being more effective due to the
3+
nadione strongly depends on the content of Au
which depends, in its turn, on the amount of gold and for the reduction of C=O bonds.
the activation temperature of the catalyst (Table 3) Using this approach and the above gold-based cata-
fact that MPV is recognized as being very selective
[
22]
while the selectivity to MDD (4) depends on the car- lysts resulted in unsatisfactory catalytic performance
rierꢃs acidity (Table 2). Thus, the samples Au4Mg-100 (e.g., on Au4Mg-100 catalyst, for example, the conver-
Adv. Synth. Catal. 2012, 354, 1301 – 1306
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Claudiu Dobrinescu et al.
COMMUNICATIONS
sion was 54.6% and selectivity to MDD was 12.1%, former, the selectivity to MDD was 84.0% for a con-
respectively). Moreover, the reaction took place only version of menadione of 22.8%.
in the presence of NaOH as an external strong base.
On the other side, the presence of this strong Brøn- a synergetic effect of strong basicity and mild acidity
ACHTUNGTRENNUNGs ted base makes the aldol condensation reaction pre- and oxide fluorides are among the best candidates
These results suggest that this reaction requires
[23]
[26,27]
dominant that is detrimental for the MDD (4) se- which are able to generate such an effect.
More-
lectivity.
The literature information
over, under these reaction conditions the acid-base
concerning the syn- surface sites of the catalysts also enable acetylation of
[
23–28]
ergetic effect of Lewis basicity and acidity may argue the menadiol obtained in the initial hydrogen-transfer
for the new metal oxide fluorides catalysts that have step.
[
29]
been recently developed in our laboratories for the
one-pot hydroacetylation of menadione.
In conclusion, we can state that the partly hydroxy-
lated MgF materials are too soft acidic materials to
2
Moreover, the acylation of alcohols and phenols promote the acetylation of the very stable menadione
was proven to take place on either basic (e.g., tertiary molecule, but strong enough for the acetylation of
phosphines, aminophosphine superbase) or acidic menadiol. The impregnation of these materials with
[
e.g., ZnCl , Sc ACHTUNGTRENNUNG( OTf) , 1,3-disubstituted tetraalkyldis- gold salts transforms them into active and selective
2 3
[
30–34]
tannoxanes] catalysts.
bi-functional catalysts for the one-pot hydroacetyla-
These oxide fluorides possess acid-base sites as tion of menadione to MDD. An even higher activity
2+
there are Lewis acid sites (undercoordinated Mg ), in combination with a higher selectivity to the target
Brønsted base sites (OH groups) and Lewis base sites product was obtained in the presence of acid-basic
(
negatively charged oxide) in different proportions metal oxide fluoride materials using a microwave-as-
À
À
and different strengths, which depends on the F /OH
ratio.
sisted hydrogen-transfer (MPV reaction) coupled with
an acetylation approach. Thus, working under micro-
[29]
For this purpose we prepared a series of magnesi- wave-assisted MPV–hydroacetylation an unprecedent-
um oxide fluoride (MgF O ) samples (with x=1.9–0.1 ed high activity and selectivity to MDD (X=40%,
x
y
and y=0.05-0.95), in which the basicity increases with S=95%) was obtained on the MgF O catalyst. As
0
.2 0.9
the amount of oxygen while the acidity increases with it was mentioned above, the catalytic performances of
the amount of fluoride (see the Supporting Informa- this sample are assigned to a synergetic effect of
[29]
tion). In this way, the Lewis acid sites of MgF O
strong Lewis basicity and mild acidity. Therefore, we
1
.9 0.05
are stronger than those of MgF O while both the strongly believe that these promising catalysts can
0.1 0.95
OH groups and the basic oxygen sites on MgF O
also be applied for other reactions that need such
0
.1 0.95
are more strongely basic than those on the other combinations.
sample (see the Supporting Information). Apparently,
in the MPV reaction in the presence of acid-base cat-
alysts, 2-propanol is adsorbed at the dual acid-base Experimental Section
sites which causes its dissociation into the correspond-
ing alkoxide, and the ketone at the adjacent acidic Menadione (97 wt%) was purchased from Across Organics.
and basic sites before the hydrogen-transfer reaction
[24]
takes place. The isopropoxide formed from 2-prop- Synthesis of Menadiol (2)
anol transfers a hydride ion that attacks the carbon
[
27]
To a suspension of menadione (2-methylnaphthoquinone,
0 g, 290 mmol) in AcOEt (400 mL) a solution of Na S O
4
atom in the carbonyl group. It is thus expected that
a solid catalyst with a proper ratio and strength of the
acid/base sites, regardless of the material type, should
be an efficient catalyst for the MPV reduction.
5
2
2
(
100 g, 574 mmol) in water (400 mL) was added at room
temperature. The resulting mixture was stirred for 0.5 h at
the same temperature. The organic layer was separated,
An initial screening of the obtained oxide fluorides washed with water (2ꢅ200 mL), and concentrated under re-
showed rather low conversions (<12%) for a reaction duced pressure. The residue was triturated with n-hexane
time of 48 h. But the reaction rate was significantly (300 mL) and the resulting crystals were collected by filtra-
tion, washed with n-hexane (100 mL), and dried under re-
increased by using a microwave-assisted hydroacyla-
tion approach. Under these conditions, for the sam-
duced pressure to give menadiol as a pale purple crystalline
[3]
1
powder (procedure in agree with Tomimatsu ). H NMR
ples with a fluoride content lower than 0.8, the reac-
tion time was shorted from 48 h to 3 h and a high se-
lectivity to MDD was obtained. The selectivities also
achieved high levels. While on MgF O , a sample
(
DMSO-d ): d=2.23 (s, 3H), 6.58 (s, 1H), 7.29–7.36 (m,
6
2
H), 7.95–8.01 (m, 2H), 8.22 (s, 1H), 9.33 (s, 1H).
0.2 0.9
Catalytic Synthesis of Menadiol Diacetate (Vitamin
K , 4)
4
that possesses mild acidity and strong basicity, a high
selectivity to MDD of 95% resulted for a 40% con-
version of menadione, on MgF O characterized by Catalytic acetylation of menadiol: In a typical procedure,
0.4 0.8,
a stronger acidity and a milder basicity than the 174 mg (1 mmol) of menadiol (MDL) were dissolved in
1304
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One-Pot Hydroacetylation of Menadione (Vitamin K ) to Menadiol Diacetate (Vitamin K )
3
4
1
3
4
mL of acetonitrile in a glass vial with a standard capacity
C NMR spectroscopy (Bruker AV 400 spectrometer, in
of 8 mL, equipped with a magnetic stirrer. To this mixture
06 mg (3 mmol) acetic anhydride (menadiol/Ac O molar
DMSO-d as solvent and Me Si as internal standard).
6
4
3
2
ratio=1/3) and 15 mg of hydroxylated fluoride (MgF2 or
Synthesis of Magnesium Oxide Fluorides
AlF ) were added. After sealing the vial, it was immersed in
3
5
0 mL of dry methanol were added to 1.56 g of magnesium
an oil bath at 808C, and the reaction mixture was stirred at
metal (Aldrich, 99.98%) in a round-bottom flask with
a reflux condenser for 3 h. An understoichiometric amount
1500 rpm for 16 h.
Catalytic hydroacetylation of menadione with molecular
of HF (n =102 mmol for MgF O and n =26 mmol for
hydrogen and thermal conditions: In a typical procedure,
72 mg (1 mmol) of menadione were dissolved in 4 mL of
1
1.6 0.2
2
MgF O ) dissolved in MeOH was added to the obtained
1
0.4 0.8
Mg
ACHTUNGTNERNU(GN OCH ) solution. After adding to this solution the nec-
acetonitrile in a stainless steel autoclave of 25 mL capacity.
To this mixture 306 mg (3 mmol) acetic anhydride (mena-
3 2
essary amount of distilled water (V =1 mL; n=52 mmol
1
and V =3.7 mL; n=207 mmol, respectively) and aging for
dione/Ac O molar ratio=1/3) and 50 mg of gold-based fluo-
2
2
1
2 h, the final gels were dried under vacuum at T=708C for
ride catalyst were added. After sealing the autoclave, 20 atm
5
h. The dry powder obtained in this way was calcined in Ar
of H were introduced. Under autoclave conditions the stir-
2
for 3 h at 3508C
ring rate was 1200 rpm, reaction temperature of 808C and
reaction time 24 h. For a new catalytic charge, the gold-
based catalyst was separated from the reaction mixture by Electrochemical Studies on the Prepared Ionic Gold-
filtration, dried in air, at room temperature, and reintro- based Fluoride Catalysts
duced for another 24 h in the same reaction mixture, under
Commercially available reagents were used without further
identical reaction conditions.
treatment: carbon powder (Aldrich, o.d.=1–2 mm), paraffin
Catalytic hydroacetylation of menadione in MPV condi-
tions (thermal conditions): 172 mg (1 mmol) of menadione
were dissolved in 6 mL of an isopropyl alcohol/acetic anhy-
dride (1/1) mixture in a glass vial with a standard capacity of
À3
oil (Sigma–Aldrich, 0.827–0.890 g·cm ), sulfuric acid
À3
(
Merck,
95–97wt%,
p.a.,
d=1.84 gcm ),
and
tetrachloroauric
basis, d=3.9 gcm at 258C).
A
H
U
G
R
N
N
(III) acid purum (Sigma–Aldrich, 50% Au
À3
1
5
0 mL, equipped with a magnetic stirrer. To this mixture
0 mg of catalyst (e.g., gold-based fluoride or oxidefluoride)
Measurements were performed on working electrodes
3+
+
[
i.e., CPE (carbon paste electrode) (Au /Au ) modified
were added. After sealing the vial, it was immersed in an oil
bath at 80–1108C, and the reaction mixture was stirred at
with ionic gold electroactive species originating from cata-
lysts prepared from a very fine powder of gold-based hy-
droxylated fluorides (e.g., Au1Mg-100, Au4Mg-100, Au4Mg-
1500 rpm for 22 h. When gold-based catalysts were used,
some tests in the same conditions but in the presence of
NaOH were also made.
Catalytic hydroacetylation of menadione in MPV condi-
tions and under microwave irradiation: Microwave-assisted
reactions were carried out with a Milestone Start S system
operating at 600 W. The stirring rate inside the reactor was
1
50, Au4Al-100) mixed with carbon paste (CP) and paraffin
oil in 1.25:2.5:1.0 wt. ratio]. A copper wire was used for
electrical contacts. Before each measurement, the surface of
the modified electrode was prepared by the following steps:
rinsed with distilled water, polished, rinsed again with dis-
tilled water, dried in air, and polished once again until
a mirror-like surface was obtained.
350 rpm. Typical experiments were carried out using 172 mg
(
1 mmol) of menadione, 408 mg (4 mmol) of Ac O (mena-
2
Electrochemical studies were performed with an electro-
chemical workstation (Autolab 12, Eco-Chemie, Utrecht,
Netherlands) coupled to a PC running the GPES software
to allow experimental control and data acquisition. The
three electrodes system consisted of the modified electrode
dione/Ac O molar ratio=1/4), 15 mL of acetonitrile and
2
2
mL of isopropyl alcohol. To this system 50 mg of catalyst
(
oxide fluoride) were added and the slurry was maintained
at 80–1408C, under stirring, for between 1 and 4 h.
The temperature inside the vessel was controlled using
either a thermocouple (thermal conditions) or a fiber optic
3+
+
[
CPE (Au /Au )] as working electrode, Ag/AgCl,KCl (3M)
as reference electrode, and a platinum wire as counter elec-
trode. All potentials are referred to Ag/AgCl,KCl (3M). As
electrolyte solution was used either 0.2N sulfuric acid or
(
microwave irradiations). Irrespective of the applied meth-
odology, after the reaction was stopped, the catalyst was
separated by filtration and the liquid phase was removed
under vacuum at 808C. The obtained product was then dis-
solved again in acetonitrile and analyzed by chromatogra-
0
.2N hydrochloric acid. Prior to each measurement the solu-
tion was degassed for 5 min with extra-pure argon gas and
an inert atmosphere was maintained by purging argon at
low pressure above the solution.
phy.
1
Menadiol monoacetate (intermediate 3)
H NMR
(
DMSO-d ): d=2.38 (s, 3H), 2.43 (s, 3H), 7.03–7.09 (m,
6
FT-IR Measurements
2
H), 7.42–7.46 (m, 1H), 7.6 (s, 1H), 7.62 (m. 1H), 7.88–7.90
m, 1H).
Menadiol diacetate (vitamin K ) H NMR (DMSO-d ):
(
The IR experiment was carried out using a Perkin–Elmer S
2000 with a spectral resolution of 4 cm . The sample was
1
À1
4
6
d=2.38 (s, 3H), 2.40 (s, 3H), 2.54 (s, 3H), 7.21–7.90 (m,
H).
Irrespective of the reaction procedure, the reaction prod-
pressed into a self-supported wafer with an area weight of
15 mg/cm . The wafer was placed in a stainless steel, low
2
5
temperature infrared cell with CaF windows. The sample
2
uct was analyzed through GC [Shimadzu instrument with
FID detection, capillary WCOT Fused Silica CP-Wax 58
was activated in the IR cell under vacuum at different tem-
peratures for 24 h. After activation the sample was cooled
(
FFAP) CB column of 50 m length] and characterized by
using liquid N in the presence of an inert gas (He, 2 mbar)
to 77 K. The CO pressure was increased stepwise. The spec-
2
1
GC-MS (ThermoElectron Corporation DSQ) and H,
Adv. Synth. Catal. 2012, 354, 1301 – 1306
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
asc.wiley-vch.de
1305

Claudiu Dobrinescu et al.
COMMUNICATIONS
tra are shown as difference of the spectrum of the sample in
the presence of CO minus the spectrum of the sample
before CO dosage. The magnesium oxide fluorides were
again treated under vacuum at 573 K for 2 h. After reactiva-
tion the sample was treated with stepwise increasing pres-
sures of CO2.
Chem. 2010, 122, 8311–8315; Angew. Chem. Int. Ed.
Angew. Chem. Int. Ed. Engl. 2010, 49, 8134–8138.
[17] F. Nea t¸ u, Z. Li, R. Richards, P. Y. Toullec, J.-P. GenÞt,
K. Dumbuya, J. M. Gottfried, H.-P. Steinrꢁck, V. I. Pꢆr-
vulescu, V. Michelet, Chem. Eur. J. 2008, 14, 9412–
9418.
[
18] E. J. Creyghton, S. D. Ganeshie, R. S. Downing, H. Van
Bekkum, J. Chem. Soc. Chem. Commun. 1995, 1859–
1
860.
References
[
19] E. J. Creyghton, S. D. Ganeshie, R. S. Downing, H. Van
Bekkum, J. Mol. Catal. A: Chem. 1997, 115, 457–472.
20] R. Cohen, C. R. Graves, S. T. Nguyen, J. M. L. Martin,
M. A. Ratner, J. Am. Chem. Soc. 2004, 126, 14796–
14803.
[21] R. B. Woodward, N. L. Wendler, F. J. Brutschy, J. Am.
Chem. Soc. 1945, 67, 1425–1429.
[22] T. Ooi, H. Ichikawa, K. Marooka, Angew. Chem. 2001,
113, 3722–3724; Angew. Chem. Int. Ed. 2001, 40, 3610–
3612.
[23] P. S. Kumbhar, J. Sanchez-Valente, J. Lopez, F. Figue-
ras, Chem. Commun. 1998, 535–536.
[24] H. Niyama, E. Echigoya, Bull. Chem. Soc. Jpn. 1972,
45, 938.
[25] J. Ruiz, C. Jimꢇnez-Sanchidriꢈn, J. M. Hidalgo, J. M.
Marinas, J. Mol. Catal. A: Chemical 2006, 246, 190–194.
[26] V. A. Ivanov, J. Bachelier, F. Audry, J. C. Lavalley, J.
Mol. Catal. 1994, 91, 45–59.
[
[
1] A. Rꢁttimann, Chimia 1986, 40, 290–306.
2] J. Zempleni, R. B. Rucker, D. B. McCormick, J. W.
Suttie, in: Handbook of Vitamins, 4th edn., Taylor &
Francis Group, London, 2007.
3] T. Ito, T. Ikemoto, T. Yamano, Y. Mizuno, K. Tomimat-
su, Tetrahedron: Asymmetry 2003, 14, 3525–3531.
4] S. C. Berk, M. Chang P. Yeh, N. Jeong, P. Knochel, Or-
ganometallics 1990, 9, 3053–3064.
[
[
[
[
[
[
[
[
5] S. Yamaguchi, M. Inoue, S. Enomoto, Bull. Chem. Soc.
Jpn. 1986, 59, 2881–2884.
6] F. Toda, K. Tanaka, H. Tange, J. Chem. Soc. Perkin
Trans. 1 1989, 1555–1556.
7] F. Weber, A. Rꢁttimann, in: Ullmannꢀs Encyclopedia of
Industrial Chemistry, Wiley-VCH, Weinheim, 2002.
8] E. G. Zhizhina, V. F. Odyakov, M. V. Simonova, Kinet.
Catal. 2008, 49, 773–781.
9] J. S. Yadav, B. V. Subba Reddy, T. Swamy K. Ragha-
vender Rao, Tetrahedron Lett. 2004, 45, 6037–6039.
[27] M. A. Aramendꢉa, V. Borau, C. Jimꢇnez, J. M. Marinas,
J. R. Ruiz, F. J. Urbano, J. Chem. Soc. Perkin Trans. 2
2002, 1122–1125.
[
10] R. A. Sheldon, J. Mol. Catal. A: Chemical 1996, 107,
5–83.
7
[
11] R. A. Sheldon, H. van Bekkum, in: Fine Chemicals
through Heterogeneous Catalysis, (Eds. R. A. Sheldon,
H. van Bekkum), Wiley-VCH, Weinheim, 2001, pp 2–3.
12] K. L. Matveev, E. G. Zhizhina, V. F. Odyakov, N. S.
Kotsarenko, V. P. Shmachkova, React. Kinet. Catal.
Lett. 1996, 57, 375–381.
[28] M. A. Aramendꢉa, V. Borau, C. Jimꢇnez, J. M. Marinas,
J. R. Ruiz, F. Urbano, Appl. Catal. A: General 2003,
249, 1–9.
[29] S. Wuttke, S. M. Coman, J. Krçhnert, F. C. Jentoft, E.
Kemnitz, Catal. Today 2010, 152, 2–10.
[30] E. Vedejs, S. T. Diver, J. Am. Chem. Soc. 1993, 115,
3358–3359.
[31] B. A. D’Sa, J. G. Verkade, J. Org. Chem. 1996, 61,
2963–2966.
[32] R. H. Baker, F. G. Bordwell, Org. Synth. 1955, 3, 141–
145.
[33] K. Ishihara, M. Kubota, H. Kurihara, H. Yamamoto, J.
Am. Chem. Soc. 1995, 117, 4413–4414.
[
[
[
[
13] S. M. Coman, S. Wuttke, A. Vimont, M. Daturi, E.
Kemnitz, Adv. Synth. Catal. 2008, 350, 2517–2524.
14] S. M. Coman, V. I. Parvulescu, S. Wuttke, E. Kemnitz,
ChemCatChem 2010, 2, 92–97.
15] S. Wuttke, S. M. Coman, G. Scholz, H. Kirmse, A.
Vimont, M. Daturi, S. L. M. Schroeder, E. Kemnitz,
Chem. Eur. J. 2008, 14, 11488–11499.
[16] A. Negoi, S. Wuttke, E. Kemnitz, D. Macovei, V. I. Par-
[34] A. Orita, K. Sakamoto, Y. Hamada, A. Mltsutome, .J.
vulescu, C. M. Teodorescu, S. M. Coman, Angew.
Otera, Tetrahedron 1999, 55, 2899–2910.
1306
asc.wiley-vch.de
ꢂ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Adv. Synth. Catal. 2012, 354, 1301 – 1306