CATALYTIC H Y D R O G E N A T I O N OF Q U I N O N E S
IN THE PRESENCE OF Pt, Pd, AND Rh C A T A L Y S T S
(UDC 542.97)
M. L. K h i d e k e i ' , B. D. P o l k o v n i k o v , A. M. T a b e r ,
a n d A. A. B a l a n d i n
N. D. Zelinskii Institute of Organic Chemistry, Academy of Sciences, USSR
and the Institute of Chemical Physics, Academy of Sciences, USSR
Translated from Izvestiya Akademti Nauk SSSR, Sertya Khimicheskaya, No. 3,
pp. 542-543, March, 1965
Original article submitted July 2, 1964
A considerable number of papers has been devoted to the homogeneous transfer of hydrogen to quinones. As a
rule [1-3], quinones, having a high oxidation-reduction potential, add hydrogen with great ease. In a number of
cases the rate of homogeneous addition of hydrogen [4-6] to quinones may be described by the equation:
leg ki / k~ ---- m (Ei -- E2) (1)
where k 1 and kz are the rate constants for the reduction of quinones, EI and E2 are the oxidation-reduction potentials,
and m is a constant [7].
It was shown recently by Musso, Figge, and Becker [8] that the hydrogenation of quinones in the presence of a
palladium catalyst (Pd/BaSO4) is also described by Eq. (1).
Hydrogenation of Quinones. Temperature 25 ~ Solvent--Dioxane, Volume
of Solvent 20 ml, Weight of Catalyst 1.0 g, 750 rpm, Atmospheric Pressure
Catalyst
Hydrogenated Wt., g i n
10 m l o f
H con-
sump.,
H con-
sump., k, ml
I
t E,* mV
compound /min
solvent ml., thJry ml., act. I
'l,4-Benzo- [
I
Pd -- B/C quinone 0,1423 64,5 : 62,5 13,2 699--700
Pd-black/C 0,1423 64,5 62,2 6,8
Pt - - B/C 0,1423 64,5 61,8 5,6
Pt-black/C 0,1423 64,5 61,0 3,4
Rh - - B/C 0,1423 64,5 62,2 3,0
Pd -- B/C Toluquinone 0,1814 72,4 64,2 10,4 644
Pd-black/C 0,1814 72,4 63,8 6,4
Pt -- B/C 0,18t4 72,4 68,4 4,2
Pt-black/C >> 0,1814 77,4 67,2 2,4
Rh -- B/C 0,1814 72,4 68,2 2,8
Pd -- B/C N aphthoquinom 0,2082 71,4 69,2 8,6 484
Pd-black/C >> 0,2082 71,4 69,0 5,2
Pt -- B/C >> 0,2082 71,4 68,4 4,6
Pt-blaek/C 0,2082 71,4 70,2 2,2
Rh -- B/C 0,2082 71,4 70,0 2,S
Pd - - B/C Duro quinone 0,2008 66,0 64,2 7,2 464
a-black/C 0,2008 56,0 62,8 4,2
Pt - - B/C )) 0,2008 56,0 63,2 6,4
Pt-black/C 0,2008 66 ;0 62,8 2,2
Rh - - B/C 0,2008 66,0 64,2 2,2
Pd - - B/C Anthraquinone 0,2104 42,4 41,2 4,6 154
Pd-black/C >) 0,2104 42,4 41,6 2,2
Pt -- B/C >> 0,2104 42,4 40,8 2,8
Pt-blaek/C 0,2104 42,4 41,2 1,2
Rh -- B/C 0,2104 42,4 40,4 1,8
* The values of the oxidation-reduction potentials, E, were taken from the
data given in [8].
519
log k I0 z It seemed of interest to determine the generality of Eq. (1) for
heterogeneous catalysts of low-temperature, liquid-phase hydrogen-
106 ation. For this we studied the hydrogenation of quinones in the pres-
ence of catalysts based on platinum, palladium, and rhodium.
8~
EX P E R I M E N T A L
60
D
The catalysts Pd--B/C, P d - b l a c k / C , P t - B / C , Rh--B/C and
uO P t - b l a c k / C were obtained by the previously described methods
[9, 10]. The quinones taken for the hydrogenation experiments were
2o first purified by sublimation.
f I [ I I I The hydrogenation was carried out in a thermostated glass
fog zlOg 6gO E, my
duck-shaped vessel at atmospheric pressure. The e x p e r i m e n t a l con-
ditions are given in the table. C o m m e r c i a l dioxane, wNch we pre-
Fig. i. Rate constants as a function of the
viously distilled, was used as the solvent.
oxidation-reduction potential in the hydro-
genation of : 1) benzoquinone; 2) naphtho-
DISCUSSION OF EXPERIMENTAL RESULTS
quinone; 3) anthraquinone; 4) toluquinone;
5) duroquinone, in dioxane, in the presence The obtained experimental data are given in the table. As
o f P d - B / C (A); P d / e ( B ) ; P t - - B / C ( C ) ;
can be seen from the table, quinones, i n t h e presence of the used
Rh--B/C (D); Pt/C (E). catalysts, are hydrogenated quantitatively to yield the corresponding
hydroquinones. The reaction is zero order. The hydrogenation rate
of all of the indicated compounds is higher on boride catalysts than on the other catalysts. Based on their hydrogen-
ation rate, the compounds can be arranged in the following order: benzoquinone --, toluquinone ~ duroquinone
-~ naphthoquinone --, anthraquinone.
A comparison of the rate constants for the hydrogenation of quinones with their oxidation-reduction potentials
reveals that the hydrogenation of quinones is described by an equation of the (1) type. The value of the constant m
is equal to -~ 0.0005 -0.0008 my -1 (Ng. 1).
It is known that a linear relationship exists between the oxidation-reduction potential of quinones and their
conjugation energies (or the difference in the conjugation energies of the quinone and the hydroquinone) [11-14].
This makes it possible to convert Eq. (1) to Eq. (2):
lg ki / k~ -~ a(~2 -- "q) (2)
where k i and k 2 are the rate constants for the reduction of the two qninones being compared, Ti and r Z are the con-
jugation energies, and a is a constant. Previously two of us had found that Eq. (2) describes the hydrogenation of
certain compounds, containing aromatic and conjugated bonds, in the presence of a rhodium catalyst [15].
SUMMARY
The hydrogenation rate of quinones in the presence of platinum, p a l l a d i u m or rhodium catalysts is linearly
dependent on the oxidation-reduction potential of the quinones, and is a particular case of the dependence of the
hydrogenation rate of organic compounds on their conjugation energy.
LITERATURE CITED
1. O. Neunhoeffer and W. Pelz, Bet., 7__2,433 (1939).
2. E. F. Rosenblatt, I. Amer. Chem. Soc., 62, 1092 (1940).
3. A. B. Fasman, V. A. Golodov, and D. V. Sokol'skli, Dokl. AN SSSR, 155, 434 (1964).
4. N. Dost, Recueil trav. chim., 7__.~1,857 (1952).
5. E. Braude, L. M. Jackman, and R. Linstead, I. Chem. Sot., 1954, 3548.
6. K. Wallenfels and M. Gellrich, Annalen, 621, 149 (1959).
7. O. Dimroth, Z. angew. Chem., 46, 571 (1933).
8. H. Musso, K. Figge, and D. J. Becket, Chem. Bet., 94, 1107 (1961).
9. A. M. Taber, N. S. Barinov, B. D. Polkovnikov, and A. A. Balandin, Izv. AN SSSR, Set. Khim., 1964, 906.
520
10. N.D. Zelinskii and A. F. Plate, Zh. Obshch. Khim., 2218, 1924.
11. M.G. Evans, Tram. Faraday Soc., 42, 113 (1946).
12. M.E. Dyatkina and Ya. K. Syrkin, Acta Physicochim. URSS, 21, 921 (1946).
13. K. Laki, Studies from the inst. of Med. Chem. Univ. Saeged., vol. 11, 49 (1942).
14. E. Berliner, J. Amer. Chem. Soc., 68, 49 (1946).
15. A.A. Balandin and M. L. Khidekel',Dokl. AN SSSR, 123, 83 (1958).
All abbreviations of periodicals in the above bibliography are letter-by-lettertransliter-
ations of the abbreviations as given in the original Russian journal S o m e or all of this peri-
odical literature may well be a v a i l a b l e in English translation. A complete l i s t o f the c o v e r - t o -
cover E n g l i s h translations appears at the back o f this issue.
521
