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Gas-Phase Reactions of Organic Compounds on Raney Nickel.

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at present how the sulfur is transferred to the cyanogen
CAS Registry number:
3, 962 11-85-7
[I] H. W. Roesky, H. Hofmann, Chem.-Ztg. 108 (1984) 231.
121 G. Weddigen (BBC AG), DOS 3 127688 (July 14, 1981, Feb. 3, 1983):
Chem. Ahstr. 98 (1983) P142984n.
[ 3 ] H . W. Roesky, K. Keller, J. W. Bats,Angew. Chem. 95 (1983) 904;Angew.
Chem. I n t . Ed. Engl. 22 (1983) 8 8 1 ; Angew. Chem. Suppl. 1983, 1323.
[4] B. Corain, M. Basato, A. Warsone, Cltirn. Ind. 61 (1979) 567.
(51 B. Corain, Coord. Chem. Rev. 47(1982) 165.
[6] Liquid SO? (20 mL) is condensed at -78OC in a pressure vessel containing 1 (1.31 g, 4.4 mmol). The mixture is subsequently heated slowly with
stirring to room temperature in order to dissolve 1 homogeneously in
SO2. The mixture is cooled once again to -78"C, and 2 (1.38 g,
26.5 mmol) is condensed into the frozen solution. After thawing, the mixture is stirred for 2 h at room temperature. A light, crystalline precipitate,
moderately soluble in SOz, is formed. After filtration, SO, and excess 2
are slowly removed, yielding colorless crystals of 3, which are very watersensitive. Yield of 3 : 0.37 g (21%): IR (Nujol): v=2200, 2125, 695. and
380 c m - ' (cf. C N stretching vibration of gaseous 2 at 2157 cm-'). Strong
Raman bands at 2356, 872, 688, 510, and 370 cm-'.
[7] F. M. Chang, M. Jansen, Angew. Chem. 96 (1984) 902; Angew. Chenz. Int.
Ed. Engl. 23 (1984) 906.
Gas-Phase Reactions of Organic Compounds on
Raney Nickel**
By Hans Bock* and Hans Peter Wow
Dedicated to Professor Gunther Wilke on the occasion
of his 60th birthday
Fig. 1. Above: perspective view of the polymeric layer cation of 3 in the crystal. C2/m, a=866.5(4), 6=836.3(3), e=819.8(4) pm, B= 122.06(3)", Z = 2
(monomers), T = - 40°C. MoKnr28,,, = 55". R = 0.039, R , = 0.043 for 550 reflections (corrected for absorption) with F > 4 o ( F ) . All atoms of the cation lie
on special positions; Ag on 0, 0 , O ; C I and NI on x, 0, z ; C2 and N2 on 0, y ,
0. The refinement was difficult because of pseudosymmetry (all reflections
with odd I are weak) and disorder of the anion. Important bond distances
[pm] and bond angles I"]: Ag-Nl 239.9(6), Ag-N2 236.4(7), N1-CI
113.8(9), N2-C2
112.8(10), CI-CI'
138.0(12), C2-C2'
152.3(9), Nl-CI-CI'
177.9(14), all other angles 90 or 180".
(CI' and C2' are equivalent atoms generated by inversion symmetry). The
transformation matrix 0- 1 0/- 1 0 O/ - 1 0 - 2 generates an apparently Fcentered orthorhombic cell (a'=836.3, b'=866.S, c ' = 1389.7 pm), which however, exhibits only monoclinic Laue symmetry. Below: projection of the
structure of 3 along the h axis (N2 and C2 lie on this axis and are therefore
difficult to recognize). The layers are clearly undulating with an Ag-NI-CI
angle of 152.3". Only one orientation of the disordered anion is shown. The
As atom lies on 0, 0, f, the F atoms, however, on general positions. Open
circles: large, Ag: medium, N ; small, C ; cross-hatched circles, As: black
points, F. Further details of the crystal structure investigation are available
on request from the Fachinformationszentrum Energie Physik Mathematik,
D-7514 Eggenstein-Leopoldshafen 2, on quoting the depository number
CSD 51 252, the names of the authors, and the journal citation.
Received: January 28, 1985;
revised: February 15, 1985 [ Z I148 IE]
German version: Angew. Chem. 97 (1985) 403
41 8
0 VCH Verlagsgesei~schajimbH, D-6940 Weinheim, 1985
Raney nickel, used advantageously both in industry1'"'
and in the laboratoryf2" as an active catalyst for liquidphase hydrogenations, is prepared from Ni/AI alloys using
concentrated caustic soda."' Physical investigations['] have
shown that the largely uniform network of pores provides
surface areas of up to 100 m2/g, depending on the method
of preparation, and contains regions of ordered Ni crystals. Moreover, the Al component affects not only the texture but also functions as an electron donor to the Ni(3d)
band. We report here the reactions of gaseous organic
compounds on solid Raney nickel."] In comparison with
the pyrolysis of such compounds on quartz wool or the catalytic decomposition on nickel turnings, these reactions
take place at much lower temperatures with marked selectivity.
The following model reactions were studied in a horizontally arranged solid-bed reactor by PE spectroscopic
analysis14' of the gas flow (see Fig. 1): the dehydrogenation
of 2-propanol, which competes with its dehydration; the
decarbonylation of methyl formate, and the elimination of
N 2 from methyl diazoacetate [Reactions (a)-(e)].
+ (H,C),C=O
+ H,C-HC=CH>
+ H,COH 2CO + 2H7
+ CO f H,C-CHO
[*I Prof. Dr. H. Bock, Dipl.-Chem. H. P. Wolf
Institut fur Anorganische Chemie der Universitat
Niederurseler Hang, D-6000 Frankfurt am Main 50 (FRG)
[**I Gas-phase reactions, Part SO. This work was supported by the Land
Hessen, the Deutsche Forschungsgemeinschaft, and the Fonds der
Chemischen Industrie. Part 49: H. Bock, B. Solouki, G. Maier, Angew.
Chem. 97 (1985) 205; Angew. Chem. Int. Ed. Engl. 24 (1985) 205.
0570-0833/85/0505-0418 $ 02.50/0
Angew. Chem. Inr. Ed. Engl. 24 (198s) No. 5
2-Propanol is approximately fifty percent dehydrogenated to acetone upon passage over a 5-cm layer of Raney
nickel at room temperature and lo-* mbar [Reaction (a)];
the hydrogen evolved can be identified by its characteristic
PES ionization pattern (Fig. 1 , middle, insert) after trapping of the condensable gases in an inserted liquid nitrogen cold trap. The elimination of H Ztakes place quantitatively at 350 K (Fig. I , bottom).
the known, favorable chemisorption of carbon monoxide['l
on the Ni surface.
The largest differences between thermal and catalytic
decomposition are found for methyl diazoacetate:"' on
quartz wool, CO is eliminated along with Nz above 523 K.
Acetaldehyde can be identified in the resulting mixture of
products PE-spectroscopically by the sharp band at
10.26 eV [Reaction (d)]. In contrast, on Raney nickel, N, is
evolved already at room temperature, and, after passage of
NN=CH-COOCH3 for several hours at 350 K, a mixture
of dimethyl maleate and dimethyl fumarate can be preparatively isolated in an inserted cold trap at 77 K [Reaction
(e)]. This surprising result presumably can be explained by
dimerization of methoxycarbonylcarbenes formed on the
nickel surface-in analogy to the reaction of diazomethane
on nickel producing ethene in the classic studies of Pettit
on the mechanism of the Fischer-Tropsch synthesis.l']
Received: February 14, 198s [Z 1168 IE]
German version: Angew. Chem Y7 (1985) 41 I
CAS Registry numbers:
(H1C)*CHOH, 67-63-0; HCOOCH,, 107-3 1-3; NN=CHCOOCH;, 6832- 162; nickel, 7440-02-0; quartz, 14808-60-7.
[I] H. P. Wolf, Diplomarbeit, Universitat Frankfurt 1984, and reference5
i s IEleV)
Fig. I. He(l) PE spectra of 2-propanol (top) and of the product mixture obtained after passage over Raney nickel at 300 K and 350 K (middle and bottom, respectively). The vibrational fine structure of the H Z band-recorded
after condensation of the products at 77 K-is shown in the two inserts.
Raney nickel lowers the required temperature for the
thermolysis of 2-propanol by more than 600 K compared
with that on quartz wool, which begins with the elimination of water at 870 K to yield propene [Reaction (b)] and
in which the dehydrogenation to acetone [Reaction (a)] can
only be detected above 970 K. The catalysis by nickel turnings of comparable particle size lowers the temperature
only 350 K.[']
Even larger temperature differences are observed for the
decarbonylation of methyl formate [Reaction (c); T,] under
the same reaction conditions:''' the elimination of C O begins at 1100 K on quartz wool, at 700 K on nickel turnings,
and at 3 7 0 K on Raney nickel. The methanol formed is
completely decomposed to C O and Hz upon raising the
temperature only another 50 K [Reaction (c); T2]. This
enormous catalytic activity, which is also observed for
other Nix contacts having large surface areas,['] is due to
A n g e w . Chem Int. Ed. Engl. 24 (19851 No. 5
therein. Experimental procedure for the Raney nickel used here: Ground
and sieved Ni/AI alloy (27 g, particle diameter I mm, Degussa, 50 wt.-'!h
Ni) is dissolved under purified NL in 30 mL of water. A solution of KOH
(5.6 g) in 30 mL of degassed H 2 0 i s added slowly under cooling. After
evolution of 4.7 L of H2 (corresponding to 3.8 g of A1 as KAIO?). the reaction is stopped by cooling to 3°C; the suspended Raney Ni is transferred
under N3 into a reaction tube stoppered with quartz wool and dried at
350°C and I rnbar for 5 h. The Raney nickel is then activated in a stream
of H, for 2 h and subsequently heated at lo-? mhar until the intense PES
ionization peak of HzO at 12.62 eV has disappeared. Analyak alter dissolving in HCI and filtering off 6.2u.0 Al2O3:Ni(electrogravimerrically)
57.4Oh; A1 (as A1201) 36.4'h.
[2] See, e.g., a) K. Winnacker, L. Kuchler: Chemi.sche Technologre. B d 6 (Organbche Technologre 11).4th Ed., Hanser, Munich 1982; K. Wei%errnel,
H. J. Arpe: Indusfrielle Organische Chemie. 2nd Ed., Verlag Chemie.
Weinheim 1978; h) S. Hiinig, C. Markl, J . Sauer: lnfeyrierfe.\ 0ryani.scl~ur
Prakfikurn, Verlag Chemie, Weinheim 1979.
[3] Review: P. Fouilloux, Appl. Cufal. 8 (1983) 1, and references cited therein.
[4] Review: H. Bock, B. Solouki, Angew. Chem. 93 (1981) 431 ; Angew Chem.
I n f . Ed. Engl. 20 (1981) 432, and references cited therein.
[5] Pumice (Merck 2441) [ I ) or active charcoal (Strem Chem. 4021) are suitable as carriers with high surface areas, 0. Breuer, Diplomarbeit, Universitat Frankfurt 1984. After impregnation with the NI'+ salt in a 5onicating bath, reduction is carried out with hydrogen at temperatures up to
720 K.
[6] For chemisorption studies on nickel [I 111 surfaces, see, e.g., G. Ertl. Angew. Chem. 88 (1976) 423; Angew. Chem. I n t . Ed. Enyl. 15 (1976) 391 or
E. L. Muetterties, ibid. 90 (1978) 577 and 17 (1978) 545, and references
cited therein.
171 R. C . Brady 111, R. Pettit, J. A m . Chem. Soc. 102 (1980) 6181; 103 (1981)
1287. See also the review of W. A. Herrmann, Angen,. Chem. Y4 (1982)
118; Angew. Ctrem. I n f . Ed. Engl. 21 (1982) 117.
The First Arsirane
By RolfAppel,* 7'homas Gaitzsch, and Falk Knoch
Dichlorophosphanes l a , b react with lithium chloro[bis(trimethylsilyl)]methanide 2 to give stable bis[bis(trimethylsilyl)methylene]phosphoranes 3."." Further reaction to give the phosphiranes 4, which is observed in the
case of bismethylenephosphoranes substituted otherwise
at the methylene C - a t o r n ~ , ' ~does
. ~ ] not take place here because of shielding by the bulky trimethylsilyl groups.
Prof. Dr. R. Appel, T. Gaitzsch, Dr. F. Knoch
Anorganisch-chemisches Institut der Universitat
Gerhard-Domagk-Strasse 1, D-5300 Bonn 1 (FRG)
0 VCH Verlagsgesellschaji mbH, 0-6940 Weinheim, 1985
0570-0833/85/0505-0419 $ 02.50/0
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nickell, raney, reaction, compounds, organiz, gas, phase
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