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Methyl Viologen Reduction with Manganese (II) - meso-tetraphenylporphyrintrisulfonic Acid and Hydrogen Evolution of Hydrogenase.

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light from a 150 W tungsten lamp. Light of wavelength less
than 390 nm was cut off by a Toshiba L-39 filter.
to be cited as
Angew. Chem. Suppl.
7982,1004- 1008
zu zitieren als
Angew. Chem. Suppl.
7982,1004-1008
OVsrlag Chemie GmbH,D-6940 Weinheim,1982
Meth 1 Viol0 en Reduction with Man anese I1 -meso-tetraphenylporphyrintrisulfonic Acid and Hydrogen Evolution of
Hydrogenase'.
When an aqueous solution containing Mn(III)-TPPS3, methyl
viologen and mercaptoethanol was irradiated, the growth of
MV',
which has characteristic absorption bands at 395 and
605 nm was observed. As shown in Fig. 1, the concentration
of MV+ increased with time after an induction period.
During the induction period the spectrum with 467 nm attributed to Mn(III)-TPPS3 decreased rapidly and new spectrum
I
i
*
d
1
By Ichiro Okura, Nguyen Kim-Thuan, and Makoto Takeuchi
Various attempts have been made to develop suitable redox
systems for photochemical utilization of solar energy.
Recent work/'/
has shown that three component systems containing a photosensitizer, an electron donor and an electron
acceptor can be used to evolve hydrogen when a suitable
catalyst is present. The photosensitizers employed almost
exclusively in these studies are ruthenium complexes except
It is desirable to explore other
for zinc porphyrins/'/.
suitable photosensitizers. In this communication, manganese
( I I ) - tetraphenylporphyrintrisulfonic acid (Mn ( I I ) TPPS3) was
used as a photosensitizer for photo-induced methyl viologen
reduction, for the studiesl3/ on the photochemistry of manganese porphyrin and phthalocyanine complexes have been
carried out and it has been shown that these complexes
undergo facile redox reactions. As reduced form of methyl
~
Dr. I . Okura, Dr. N. Kim-Thuan, M. Takeuchi
Department of Chemical Engineering, Tokyo Institute of
Technology, Meguro-ku, Tokyo, 152 (Japan)
+* We thank Professor Tominaga Keii and Professor Yoshio
Ono for stimulating and helpful discussions.
-
1004
viologen (MV')
is known to produce
of a suitable catalyst, an attempt
water to hydrogen using a modified
containing a Mn(I1) -TPPS3 - methyl
tion system and hydrogenase.
hydrogen in the presence
was also made to reduce
electron transfer.system
viologen' photo-irradia-
Mn(II)-TPPS3 was synthesized by refluxing TPPS3 (4.3 mg)
and manganese acetate (10.4 mg) in methanol (20 cm3) for
2.5 h. The formation of Mn(III)-TPPS3 was monitored by the
following spectra changes. During the reaction the growth
of Mn(III)-TPPS3, which has a characteristic absorption
i
band at 467 nm, was observed and the absorbance at 417 m
of the solution containing TPPS3 and manganese acetate decreased gradually with isosbestic points at 390 and 430 nm
and became extinct after 2 h. The reaction mixture was
used in the following experiments without further purification. Although the reagent, manganese acetate, was not
separated from Mn(III)-TPPS3, it has been confirmed that
manganese acetate has no influence on the photo-reduction
of methyl viologen. ' The enzyme, hydrogenase from D. vulgaris
The concentrawas purified according to Yagi's method"'.
tion of hydrogenase is not known but it has the ability to
produce 8.5 x
mol of hydrogen using the reaction system: hydrogenase (0.1 cm3) + methyl viologen (8.1 x
mol) + Na2S204 (2.0 x lo-' mol) in 3 cm3 of 0 . 0 2 m o ~ d r n - ~
phosphate buffer (pH 7.0) at 30°C for 20 min.
A typical experiment was performed as follows under anaerobic conditions at 30'C.
To 1.31 x lo-' mol of Mn(II1)TPPS3, 8.12 x
mo1 of methyl viologen and 5.43 x
mol of mercaptoethanol as a reducing agent in water, if
necessary, 0 . 5 cm3 of hydrogenase was added; the volume of
the mixture was adjusted to 6 cm3 with 0.1 mol.dm-3 TrisHC1 buffer (pH 7.0).
In the photolysis with steady irradiation, the sample, in a Pyrex cell was irradiated with
- 1005
-
0
10
20
Time / min
Fig. 1.
Time dependence of the concentration of Mn(I1)TPPS3 and MV+; 0 : Mn(II)-TPPS3,
0 : Mn(II1)TPPS3, 0 : MV*; Solutions containing 1.31 x lo-'
mol of methyl
mol of Mn(III)-TPPS3, 8.12 x
viologen and 5.43 x
no1 of mercaptoethanol
is irradiated at 30°C.
- 1006 -
with 435 nm appeared. When the spectrum appeared the reduction of methyl viologen started and the spectrum remained unchanged afterwards as shown in Fig. 1. As the
reduction of Mn(III)-TPPS3 with dithionite yielded the
same spectrum, the photosensitizer with 435 nm for methyl
viologen reduction can be attributed to divalent manganese
Aeration of the product leads to
porphyrin, Mn(II)-TPPS5.
immediate reconversion t o the starting compound, Mn(II1)TPPS3, without loss.
When hydrogenase (0.5 cm3) was added in the system containing Mn(III)-TPPS3 (4.64 x lo-' mol), methyl viologen
(7.26 x
mol) and mercaptoethanol (5.43 x
mol),
hydrogen evolution was observed. The volume of the mixture
was adjusted to 6 cm3. The amount of hydrogen evolved for
2 h and 4 h irradiation was 1.23 umol and 1.89 umol, respectively. No hydrogen evolution was observed when any
component of the system was omitted. Hydrogen evolution
(1.08 wool) was also observed by 4 h irradiation of sunlight instead of the tungsten lamp.
/1/ J. M. Lehn, J . P. Sauvage, Nouv. J. Chim. 1 (1977) 449;
M. Kirch, J. M. Lehn, J. P. Sauvage, Helv. Chim. Acta
62 (1979) 1345; h. Kalyanasundaram, J. Kiwi, M. Gratzel,
ibid 61 (1978) 2 7 2 0 ; K. Kalyanasundararn, M. Gratzel, JChem. SOC. Chem. Comun. 1979, 1137; A. Moradpour, E.
Amouyal, P. Keller, H. Kagan, Nouv. J. Chim. 2 (1978)
547; A . I . Krasna, Photochem. Photobiol. 29 (1979) 267;
I . Okura. N. Kim-Thuan, J. Mol. Catal. 5 (1979) 311; I .
Okura, S. Nakamura, N. Kim-Thuan. K. Nakamura,
(1979) 261; I . Okura, N. Kim-Thuan, J . Chem. Res. (S)
1979, 344; I. Okura, N. Kim-Thuan, J. Chem. SOC. Chem.
Commun. 1980, 84; I . Okura, N. Kim-Thuan, Chem. Lett.
1980, 1511; I . Okura, N. Kim-Thuan, J. Chem. SOC.
Faraday Trans. I 76 (1980) 2209.
- 1007 -
K. Takwna, M. Kajiwara, T . Matsuo. Chem. L e t t . 1977,
1199; I. Okura, N. Kim-Thuan, J . Mol. C a t a l . 6 (1979)
2 2 7 ; I . Okura. M. Takeuchi, N. Kim-Thuan, Chem. L e t t .
1980, 765; K . Kalyanasundaram, M. G r a t z e l , Helv. Chim.
Acta 63 (1980) 478; J . R. Darwent, J . Chem. SOC. Chem.
Commun. 1980, 805.
/3/ G . Engelsma, A. Yamamoto, E. Markham, M. C a l v i n , JPhys. Chem. 66 (1962) 2517; M. C a l v i n , P. A . Loach,
Biochemistry 2 (1963) 361; A. Harriman, G. P o r t e r , JChem. SOC. Faraday Trans. I1 75 (1979) 1543; I . A .
Duncan, A. Harriman, G. P o r t e r , i b i d 76 (1980) 1415; A .
Harriman, G. P o r t e r , i b i d 76 (1980) 1429.
/ 4 / T. Yagi, J. Biochem. 68 (1970) 649.
/2/
-
--1
D i e a c i d e Methylengruppe d e r D i a z a s i l a c y c l o p e n t e n e e r l a u b t
i n Reaktionen m i t Elementhalogeniden S u b s t i t u t i o n e n am Ring”’!
I n F a l l d e r l i t h i i e r t e n fluorsilylsubstituierten Ringe kann
auf Grund von i s o l i e r t e n Cycloaddukten d a s i n t e r m e d i a r e Auft r e t e n von
Bindungen w a h r s c h e i n l i c h gemacht werdei@.
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Bindungen des zweifach k o o r d i n i e r t e n Phos-
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I n d e r Reaktion des l i t h i i e r t e n T r i m e t h y l s i l y l s u b s t i t u -
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m i t tet-Butyldichlorphosphan
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to be cited as
zu zitieren als
Angew. Chem. Suppl.
5-
Angew. Chem. Suppl.
7982,1009-1015
7982,1009- 1015
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07214227/82/LX-%-1~02.5010
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d i e i n t e n s i v rot-orange gefBrbte Verbindung
W i l l i a m Clegg, Martin Haase, Michael Hesse, W e K l i n g e b i e l
und George M.
Sheldrick
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P h ~ s p h i r a n e ’ ~ ‘3’ gelang 1978 auch d i e D a r s t e l l u n g von
d i e e x o c y c l i s c h e Coppelbindungen am Ring besitZen”’
und Ver-
bindungen, d i e s i c h durch den E r s a t z des R i n g k o h l e n s t o f f s
durch s e i n e h8heren Homologen a u s z e i c h n e d ” .
W i r s t e l l e n e i n auf einem n e u a r t i g e n Syntheseweg e r h a l t e n e s
v o r , d e s s e n Kohlenstoffatom den D r e i r i n g m i t
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Prof. G.M. S h e l d r i c k , Priv.-Doz. D r . U. K l i n g e b i e l ,
D r . W. Clegg, Dipl.Chern. 1. Hesse, M. Haase, I n s t i t u t
f u r Anorganische Chernie d e r U n i v e r s i t a t , T a m n n s t r a s s e 4 ,
D-3400 G8ttingen
**
Diese A r b e i t wurde von d e r Deutschen Forschungsgemeins c h a f t und den Fonds d e r Chemischen I n d u s t r i e u n t e r stutzt.
c\Q
-c&;
1-4,
Eine Ursache f i i r d a s s p e z i e l l b e i e - b u t y l s u b s t i t u i e r t e n
Verbindungen des w e i f a c h k o o r d i n i e r t e n Phosphors zu beobachtende c a r b e n l h n l i c h e V e r h a l t e n . i s t i n d e r e r h 6 h t e n Nucleophil i e d e s Phosphors, h e r v o r g e r u f e n durch d i e t e e - B u t y l g r u p p ,
zu sehen.
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1009 -
- 1011 -
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acid, hydrogen, meso, methyl, hydrogenase, reduction, evolution, viologen, tetraphenylporphyrintrisulfonic, manganese
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