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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.
OVsrlag Chemie GmbH,D-6940 Weinheim,1982
Meth 1 Viol0 en Reduction with Man anese I1 -meso-tetraphenylporphyrintrisulfonic Acid and Hydrogen Evolution of
When an aqueous solution containing Mn(III)-TPPS3, methyl
viologen and mercaptoethanol was irradiated, the growth of
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
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.
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
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 TrisHC1 buffer (pH 7.0).
In the photolysis with steady irradiation, the sample, in a Pyrex cell was irradiated with
- 1005
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.
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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
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.
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@.
S i l y l a m i n s u b s t i t u i e r t e Phosphane fUhren z u r Bildung exocycReceived A p r i l 1 5 , 1981 /Z 103 S/
l i s c h e r )N-P=C<
Bindungen des zweifach k o o r d i n i e r t e n Phos-
phor~’~’ am Ring. H i e r konnte b i s h e r k e i n e , den 1,3-Disilacyclobutanen v e r g l e i c h b a r e C y c l o a d d i t i o n b e o b a c h t e t werdenI7!
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 -
i e r t e n Ringes
2 ’7’
m i t tet-Butyldichlorphosphan
L8sung das S u b s t i t u t i o n s p r o d u k t
ist i n
nachweisbar, das beim ver-
such d e r d e s t i l l a t i v e n Reinigung s t l n d i g C h l o r t r i m e t h y l s i l a n
1. C 4 H g L i
2. CMe3PC12
1. -C4H10
2. - L i C l
- 1008 -
- 1010 -
to be cited as
zu zitieren als
Angew. Chem. Suppl.
Angew. Chem. Suppl.
7982,1009- 1015
0 Verlag Chemie GmbH. D+40 Weinheim, 1982
Ein s p i r o c y c l i s c h e s Diphosphiran
D i e nach v e r g l e i c h b a r e n R e a k t i ~ n e n ’ ~ ’
zu e w a r t e n d e Verbin-
CMe3PC12 jedoch n i c h t nachgewiesen werden. Neben
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.
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
einem D i a z a s i l a c y c l o p e n t e n s p i r o c y c l i s c h v e r k n u p f t .
i s o l i e r t , de-
Diph~sphiranen/~“’. S e i t h e r wurden Diphosphirane b e s c h r i e b e n ,
ren S t r u k t u r r o e n t g e n k r i s t a l l o g r a p h i s c h ermi t t e I t wurde
L - 4
Nach der Synthese s t a b i l e r Cyclotriphosphane” r2’
2 mit
;w i r d
kann i n den Umsetzungen von l i t h i i e r t e m
A l s Bildungsmechanismus von
w i r d a n a l o g d e r (2+1)
C y c l o a d d i t i o n d e s 1,2-Bis ( t e r t - b u t y l ) iminopho~phans’~’ d i e
(2+1)Cycloaddition zweier Molekiile
miter Abspaltung e i n e s
d i m e r i s i e r e n d e n 1.2-Diaza-3-sila-5-cyclopenten-4-carbens
e i n e s r e l a t i v s t a b i l e n 6n-Systems
1 +
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.
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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acid, hydrogen, meso, methyl, hydrogenase, reduction, evolution, viologen, tetraphenylporphyrintrisulfonic, manganese
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