Synthetical applications of activated metal catalysts. XXI. The formation of carbazole from aniline and related compounds in the presence of degassed Raney nickel

1964 ◽  
Vol 17 (3) ◽  
pp. 347 ◽  
Author(s):  
GDF Jackson ◽  
WHF Sasse
Keyword(s):  
Raney Nickel ◽  
Metal Catalysts ◽  
Related Compounds

Trace amounts of carbazole are formed by the action of W-7J Raney nickel on aniline, diphenylamine, 2,2'-diaminobiphenyl, and 2-aminobiphenyl. Aniline yields also N-cyclohexylaniline, diphenylamine, 2,2'-diaminobiphenyl, and 2-aminobiphenyl; 2,2'-diaminobiphenyl gave 2-aminobiphenyl also. Carbazole was not detectably affected by the catalyst. These results suggest that aniline is slowly converted to carbazole (a) by way of diphenylamine; (b) by way of 2,2'-diamino- biphenyl and 2-aminobiphenyl; and (c) by way of 2,2'-diaminobiphenyl. The last route appears to be the most efficient one.

Synthetical applications of activated metal catalysts. XXV. The hydrogenolysis of some phenyl derivatives of silicon by Raney nickel

1966 ◽  
Vol 19 (10) ◽  
pp. 1897 ◽  
Author(s):  
WHF Sasse ◽  
KO Wade
Keyword(s):  
Raney Nickel ◽  
Silicon Atom ◽  
Atmospheric Pressure ◽  
Nickel Catalysts ◽  
Metal Catalysts ◽  
Derivatives Of ◽  
Related Compounds ◽  
Raney Cobalt

Tetraphenylsilane and 11 related compounds have been cleaved by treatment at atmospheric pressure with Raney nickel catalysts to give mixtures of benzene and cyclohexane. Yields exceeding 90% are obtained with degassed Raney nickel and silanes. Silanols and siloxanes are less readily spilt. The presence of methanol in the reaction mixtures retards the fission of silicon-phenyl bonds. Tetracyclo-hexylsilane, cyclohexyltrimethylsilane, and hexa(n-hexyl)disiloxane did not react detectably with Raney nickel. Raney cobalt had no effect on tetraphenylsilane. A mechanism for the new reaction is discussed which involves chemisorption via the silicon atom, ejection of a phenyl anion, and hydrogenolysis of the absorbed triphenylsilyl species.

Synthesis of 5-n-alkylresorcinol dimethyl ethers and related compounds via substituted thiophens

1971 ◽  
Vol 24 (12) ◽  
pp. 2655 ◽  
Author(s):  
D Buddhasukh ◽  
JR Cannon ◽  
BW Metcalf ◽  
AJ Power
Keyword(s):  
Raney Nickel ◽  
Stannic Chloride ◽  
Electrophilic Attack ◽  
Related Compounds ◽  
By Products

5-n-Alkylresorcinol dimethyl ethers have been synthesized by desulphurization of 2-(3,5-dimethoxybenzyl)-5-n-alkylthiophens with Raney nickel. The method has been adapted to the preparation of 9-(3,6- dimethoxyphenyl)nonyl alcohol which has been converted into both (2)- and (E)-15-(3,5-dimethoxyphenyl)pentadec-5-ene. ��� Friedel-Crafts acylation of 2-(3,5-dimethoxybenzyl)thiophen with n- hexoyl chloride, or with n-decoyl chloride, in the presence of stannic chloride, yielded the expected 2-(3,6-dimethoxybenzyl)-5-n- acylthiophens, but by-products were formed as the result of competing electrophilic attack on the 3,5-dimethoxybenzyl moiety. The chief by- products, which arise by subsequent Bradsher cyclodehydration, have been formulated as 5,7-dimethoxy-4-n-alkylnaphtho[2,3-b]thiophens. ��� An attempt to synthesize 1,14-bis(3,5-dimethoxyphenyl)tetradecane from 2,2?,6?,2?-terthienyl by an adaptation of this method was unsuccessful.

Synthetical Applications of Activated Metal Catalysts. XVI. The Role of Hydrogen in the Formation of 2,2'-Bipyridyl from Pyridine under the Influence of Degassed Raney Nickel

1963 ◽  
Vol 16 (1) ◽  
pp. 14 ◽  
Author(s):  
WHF Sasse ◽  
CP Whittle
Keyword(s):  
Raney Nickel ◽  
Nickel Catalysts ◽  
Nickel Atom ◽  
Metal Catalysts ◽  
Published Data ◽  
Hydrogen Atoms ◽  
Adsorbed Pyridine

The efficiency of W7 Raney nickel catalysts degassed between 30 and 400�C in the preparation of 2,2'-bipyridyl has been examined. The highest activities are observed with catalysts which have been degassed at 200�C, and these catalysts arc up to 20% more efficient than catalysts previously used and degassed at 100�C. The results obtained are compared with published data concerning the hydrogen contents of degassed Raney nickel catalysts (Kokes and Emmett 1959, 1960). This shows that catalysts which are virtually free of hydrogen are only 25% less efficient than catalysts degassed at l00�C (containing 65 to 70% of their original hydrogen). Because of this finding a new mechanism is proposed in which the adsorbed pyridine is activated by the transfer of an electron from the catalyst. On stereochemical grounds it is proposed that meso-2,2'-dihydro-2,2'-bipyridyl with axially disposed hydrogen atoms at the 2,2'-positions and bonded via both nitrogen atoms to one nickel atom is the energetically most favoured intermediate.

Raney metal catalysts: I. comparative properties of raney nickel proceeding from Ni-Ai intermetallic phases

1984 ◽  
Vol 9 (1) ◽  
pp. 69-83 ◽  
Author(s):  
S. Sane ◽  
J.M. Bonnier ◽  
J.P. Damon ◽  
J. Masson
Keyword(s):  
Raney Nickel ◽  
Intermetallic Phases ◽  
Metal Catalysts

Lignin and related compounds. I. A comparative study of catalysts for lignin hydrogenolysis

1969 ◽  
Vol 47 (5) ◽  
pp. 723-727 ◽  
Author(s):  
J. M. Pepper ◽  
Y. W. Lee
Keyword(s):  
Comparative Study ◽  
Raney Nickel ◽  
Lignin Degradation ◽  
Soluble Fraction ◽  
Degradation Products ◽  
Quantitative Estimation ◽  
Liquid Chromatographic Separation ◽  
Lignin Degradation Products ◽  
Liquid Chromatographic ◽  
Related Compounds

A detailed comparative study has been made of the effectiveness of various catalysts for the hydrogenolysis of spruce wood lignin. The catalysts studied were Raney nickel, 10% palladium–charcoal, 5% rhodium–charcoal, 5% rhodium–alumina, 5% ruthenium–charcoal, and 5% ruthenium–alumina. Lignin degradation products were obtained initially as a chloroform-soluble fraction which was then divided and studied as diethyl ether-soluble and -insoluble fractions. Gas–liquid chromatographic separation of the ether-soluble fraction made possible the characterization and quantitative estimation of many of the lower molecular weight lignin degradation products.The data indicate that rhodium, palladium, and a limited amount of Raney nickel produce similar results as do ruthenium and an excess of Raney nickel; however, with the latter catalysts the degradation is more severe. In particular, rhodium–charcoal and palladium–charcoal appear to offer interesting advantages as catalysts for lignin hydrogenolysis.

Synthetical applications of activated metal catalysts. XXII. The desulphurization of 2,5-Diphenyl-1,4-dithiin

1964 ◽  
Vol 17 (3) ◽  
pp. 353 ◽  
Author(s):  
GM Badger ◽  
P Cheuychit ◽  
WHF Sasse
Keyword(s):  
Raney Nickel ◽  
Hydrogen Content ◽  
Metal Catalysts ◽  
Hydrocarbon Fraction ◽  
Sulphur Atom ◽  
Cis And Trans

The desulphurization of 2,5-diphenyl-1,4-dithiin (II) with a hydrogen-poor Raney nickel (W-7J Raney nickel) has been shown to give 2,4-diphenylthiophen together with three hydrocarbons, viz. cis- and trans-1,3-diphenylbuta-1,3-diene, and 1,3-diphenylcyclobut-1-ene. In another experiment with a Raney nickel having a higher hydrogen content, the hydrocarbon fraction was found to be 1,3-diphenylbut-2- ene. It has been concluded that chemisorption via one sulphur atom leads to 2,4-diphenylthiophen, but that chemisorption via both sulphur atoms leads to the intermediate diradicals (VI) which subsequently react further to give the observed hydrocarbon products.

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