Direct Reduction of Alcohols:  Highly Chemoselective Reducing System for Secondary or Tertiary Alcohols Using Chlorodiphenylsilane with a Catalytic Amount of Indium Trichloride

2001 ◽  
Vol 66 (23) ◽  
pp. 7741-7744 ◽  
Author(s):  
Makoto Yasuda ◽  
Yoshiyuki Onishi ◽  
Masako Ueba ◽  
Takashi Miyai ◽  
Akio Baba
Keyword(s):  
Direct Reduction ◽  
Catalytic Amount ◽  
Tertiary Alcohols

Heterogeneous Catalysis, VI Direct Reduction of Alcohols to Hydro- carbons [1]

1982 ◽  
Vol 37 (3) ◽  
pp. 392-394 ◽  
Author(s):  
Wilhelm F. Maier ◽  
Irina Thies ◽  
Paul von Ragué Schleyer
Keyword(s):  
Heterogeneous Catalysis ◽  
Gas Phase ◽  
Direct Reduction ◽  
Primary Alcohols ◽  
Tertiary Alcohols

Abstract Secondary and tertiary alcohols are converted cleanly to the parent hydrocarbons in the gas phase with H2 in the presence of a Ni/Al2O3 catalyst at 190 °C. Primary alcohols are de-hydroxymethylated; e.g., 1-hydroxymethylada-mantane (4) gives adamantane (1). Alumina alone, in the absence of Ni, results in the formation of homoadamantane (5) from 4.

β Elimination of a phosphonate group from an alkoxyl radical — Intramolecular acylation using acylphosphonate derivatives as carbonyl group acceptors

2005 ◽  
Vol 83 (6-7) ◽  
pp. 917-921 ◽  
Author(s):  
Chang Ho Cho ◽  
Sunggak Kim
Keyword(s):  
Carbonyl Group ◽  
Direct Reduction ◽  
Catalytic Amount ◽  
Radical Cyclization ◽  
Alkoxyl Radical ◽  
Phosphonate Group ◽  
Radical Acceptor ◽  
Ready Access ◽  
First Time ◽  
Cyclohexanone Derivative

The possibility of β elimination of a phosphonate group in radical reactions was studied. The facile β elimination of the phosphonate group from an alkoxyl radical was observed for the first time, whereas the β elimination of the phosphonate group from an aminyl and an alkyl radical did not occur. On the basis of our findings, the use of an acylphosphonate as a carbonyl group radical acceptor was investigated. Radical cyclization of the acylphosphonate in the presence of hexamethylditin in benzene at 300 nm for 2 h gave a cyclopentanone or a cyclohexanone derivative in good yield without the formation of a direct reduction product. The reaction can be carried out in the presence of a catalytic amount of hexamethylditin (0.2 equiv.) under similar conditions. In addition, an alkyl phosphonothiolformate group can act as an alkylthiocarbonyl group equivalent radical acceptor, providing ready access to a thiolactone synthesis.Key words: radical, β elimination, acylation, cyclization, acylphosphonate.

Indium(III) triflate — a catalyst for greener aromatic alkylation reactions

2013 ◽  
Vol 91 (12) ◽  
pp. 1262-1265 ◽  
Author(s):  
Ryan Mack ◽  
Grant Askins ◽  
Jacob Lowry ◽  
Nathan Hurley ◽  
Perry C. Reeves
Keyword(s):  
Ionic Liquid ◽  
Aromatic Compounds ◽  
Energy Efficient ◽  
Alkylating Agents ◽  
Catalytic Amount ◽  
Significant Loss ◽  
Primary Alcohols ◽  
Tertiary Alcohols ◽  
Alkylation Reactions ◽  
Environmentally Friendly Method

An environmentally friendly method for alkylating aromatic compounds with simple alcohols in the presence of a catalytic amount of indium(III) triflate is reported. Ionic liquids are used as solvents and energy-efficient heating is provided by microwave radiation. Good yields are obtained with benzyl, secondary, and tertiary alcohols. Simple primary alcohols are not effective alkylating agents under these conditions. With tertiary alcohols, activated aromatic compounds such as toluene and anisole must be used to obtain good yields. The catalyst, which is immobilized in a water-insoluble ionic liquid, can be easily recycled without significant loss of activity.

ON THE PROCESSING OF HEMATITE RAW MATERIALS AT THE KRYVOROZHSK MINING AND PROCESSING PLANT OF OXIDIZED ORE ON TECHNOLOGY OF DIRECT RECOVERY ITmk3

2018 ◽  
pp. 32-37
Author(s):  
P.I. Loboda ◽  
Younes Razaz ◽  
S. Grishchenko
Keyword(s):  
Magnetic Properties ◽  
Cast Iron ◽  
Iron Content ◽  
Raw Materials ◽  
Direct Reduction ◽  
Processing Plant ◽  
High Iron Content ◽  
High Iron ◽  
Direct Restoration ◽  
First Time

Purpose. To substantiate the efficiency of processing hematite raw materials at the Krivoy Rog Mining and Processing Plant of Oxidized Ores using the direct reduction technology itmk3®. Metodology. Analysis of the results of the itmk3® direct restoration technology developed by Kobe Steel Ltd., Japan and Hares Engineering GmbX, Austria, with a view to using it to process Krivbass hematite ores into granulated iron (so-called “nuggets”). Findings. The involvement in the production of hematite ores (oxidized quartzite) of Krivbass with high iron content, but with low magnetic properties for their processing into granular cast iron is grounded. Originality. The use of itmk3® direct reduction technology from Kobe Steel Ltd., Japan and Hares Engineering GmbH, Austria for the processing of Krivbass hematite ores into granular cast iron is justified for the first time. Practical value. The efficiency of the use of hematite ores (oxidized quartzite) has been substantiated, which can significantly reduce the costs in the mining cycle for the economical production of metallurgical products.

Reversing Reactivity: Stereoselective Desulfurative β-O-Glycosylation of Anomeric Thiosugars with Carboxylic Acids Under Copper or Cobalt Catalysis

2019 ◽  
Author(s):  
Samir Messaoudi ◽  
Nedjwa Bennai ◽  
Amelie Chabrier ◽  
Maha Fatthalla ◽  
Expédite Yen-Pon ◽  
...  
Keyword(s):  
Carboxylic Acids ◽  
Late Stage ◽  
Catalytic Amount ◽  
Broad Scope ◽  
Wide Range ◽  
Glycosylation Reaction

We have discovered a new mode of reactivity of 1-thiosugars in the presence of Cu(II) or Co(II) for a stereoselective <i>O</i>-glycosylation reaction. The process involves the use of a catalytic amount of Cu(acac)2 or Co(acac)2 and Ag2CO3 as an oxidant in α,α,α-trifluorotoluene (TFT). Moreover, this protocol turned out to have a broad scope, allowing to prepare a wide range of com-plex substituted <i>O</i>-glycoside esters in good to excellent yields with an exclusive β-selectivity. The late-stage modification of phar-maceuticals by this method was also demonstrated.

Photocatalytic Alkylation of Pyrroles and Indoles with α-Diazo Esters

2019 ◽  
Author(s):  
Łukasz Ciszewski ◽  
Jakub Durka ◽  
Dorota Gryko
Keyword(s):  
Aromatic Compounds ◽  
Reaction Pathway ◽  
Alkylating Agents ◽  
Catalytic Amount ◽  
Radical Formation ◽  
Reaction Selectivity ◽  
Diazo Esters ◽  
Electron Withdrawing Substituents

This article describes direct photoalkylation of electron-rich aromatic compounds with diazo compoiunds. C-2 alkylated indoles and pyrroles are obtained with good yields even though the photocatalyst (Ru(bpy)3Cl2) loading is as low as 0.075 mol %. For substrates bearing electron-withdrawing substituents the addition of a catalytic amount of N,N-dimethyl-4-methoxyaniline is required. Both EWG-EWG and EWG-EDG substituted diazo esters are suitable as alkylating agents. The reaction selectivity and mechanistic experiments suggest that carbenes/carbenoid intermediates are not involved in the reaction pathway, instead radical formation is proposed.

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