The Preparation of 1,1′-Carbonyl- and 1,1′-Sulfinyl-dipyrazoles and their Reactions with Carbonyl Compounds

1973 ◽  
Vol 51 (15) ◽  
pp. 2448-2451 ◽  
Author(s):  
K. I. The ◽  
L. K. Peterson ◽  
E. Kiehlmann
Keyword(s):  
Carbon Dioxide ◽  
Sulfur Dioxide ◽  
Carbonyl Compounds ◽  
Metal Ion ◽  
Aldehydes And Ketones

The compounds 1,1′-carbonylbis(3-methylpyrazole) (1), 1,1′-carbonylbis(3,5-dimethylpyrazole) (2), and 1,1′-sulfinyldipyrazole (3) have been prepared. They react with aldehydes and ketones in the presence of metal ion catalysts to form 1,1′-alkylidenedipyrazoles together with carbon dioxide, from 1 and 2, or sulfur dioxide, from 3. Tetrapyrazol-1-ylmethane results from the pyrolysis at 200° of 1,1′-carbonyldipyrazole in the presence of cobalt(II) chloride.

The Mechanism of the Transition Metal-catalyzed Reaction of 1,1′-Carbonyldipyrazoles with Aldehydes and Ketones

1974 ◽  
Vol 52 (13) ◽  
pp. 2367-2374 ◽  
Author(s):  
L. K. Peterson ◽  
E. Kiehlmann ◽  
A. R. Sanger ◽  
K. I. Thé
Keyword(s):  
Carbon Dioxide ◽  
Metal Ion ◽  
Substituent Effects ◽  
Amide Bond ◽  
Reaction Conditions ◽  
Aldehydes And Ketones ◽  
Amide Carbonyl ◽  
Amide Carbonyl Group ◽  
Metal Catalyzed ◽  
Metal Ion Exchange

The metal-catalyzed reaction of 1,1′-carbonyldipyrazoles with aldehydes or ketones to give 1,1′-alkylidenedipyrazoles and carbon dioxide, the latter being derived from the amide carbonyl group as shown by labeling experiments, is sensitive to electronic and to steric substituent effects. Under comparable reaction conditions, 1,1′-carbonyldiimidazole, N-acetylpyrazole, and 1-pyrazole-N,N-diethylcarbonamide do not react with acetone while pyrazole-1-carbo(N′-phenylhydrazide) yields an anilino isocyanate dimer. These results are interpreted in terms of a mechanism that involves coordination of the metal ion at the 2,2′-nitrogen atoms of the pyrazole rings and heterolytic cleavage of an amide bond, followed by formation of a carbamate intermediate, decarboxylation, and metal ion exchange. Unsymmetrically substituted 1,1′-carbonyldipyrazoles were found to equilibrate thermally with their respective symmetrical analogs by an intermolecular exchange mechanism.

scholarly journals Copper(I) Chloride/Kieselguhr: A Versatile Catalyst for Oxidation of Alkyl Halides and Alkyl Tosylates to the Carbonyl Compounds

1999 ◽  
Vol 23 (7) ◽  
pp. 434-435
Author(s):  
Mohammed M. Hashemi ◽  
Yousef Ahmadi Beni
Keyword(s):  
Carbonyl Compounds ◽  
Alkyl Halides ◽  
Aldehydes And Ketones ◽  
High Yields

Copper(I) Chloride adsorbed on Kieselguhr in the presence of oxygen catalyses oxidation of alkyl halides and alkyl tosylates to the aldehydes and ketones in high yields.

Carbon dioxide permeation through ceramic-carbonate dual-phase membrane-effects of sulfur dioxide

2017 ◽  
Vol 540 ◽  
pp. 477-484 ◽  
Author(s):  
Tianjia Chen ◽  
Baolong Yu ◽  
Yicheng Zhao ◽  
Yongdan Li ◽  
Y.S. Lin
Keyword(s):  
Carbon Dioxide ◽  
Sulfur Dioxide ◽  
Dual Phase ◽  
Membrane Effects

scholarly journals Michael addition of carbonyl compounds to nitroolefins under the catalysis of new pyrrolidine-based bifunctional organocatalysts

2018 ◽  
Vol 16 (6) ◽  
pp. 924-935 ◽  
Author(s):  
A. Castán ◽  
R. Badorrey ◽  
J. A. Gálvez ◽  
P. López-Ram-de-Víu ◽  
M. D. Díaz-de-Villegas
Keyword(s):  
Michael Addition ◽  
Carbonyl Compounds ◽  
Asymmetric Michael Addition ◽  
Aldehydes And Ketones

Novel bifunctional pyrrolidine-based organocatalysts applicable for the asymmetric Michael addition of aldehydes and ketones to nitroolefins have been developed.

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