The present invention generally relates to quinoxaline compounds having Formula 1 or Formula 2 wherein the variables are as defined herein, and methods of using them.
A process for the preparation of 2-chloro-6-haloquinoxaline compounds from the corresponding 4-halo-2-nitroaniline utilizing four reaction steps with generally compatible solvents and reagents with volatile by-products to minimize the isolation and purification of intermediates has been developed.
The present invention relates to a process for preparing a 2-quinoxalinol compound, in the free form, of the following formula (II); ##STR1## wherein R is hydrogen, halogen or a trifluoromethyl group, which comprises reducing a 2-quinoxalinol-4-oxide compound, in the free form, of the following formula (I); ##STR2## wherein R is a defined above, with hydrazine in the presence of a Raney catalyst and a hydroxide of an alkali metal or an alkaline earth metal or ammonium hydroxide.
Process for the selective reduction of 2-quinoxaline-4-oxides
申请人:UNIROYAL CHEMICAL COMPANY, Inc.
公开号:EP0295797A2
公开(公告)日:1988-12-21
Certain 2-quinoxalinol-4-oxides are selectively reduced to form 2-quinoxalinols employing hydrogen as a reducing agent by reacting such 2-quinoxalinol-4-oxides with a catalyst selected from the group consisting of sulfided platinum, sulfided palladium, sulfided rhodium and sulfided ruthenium.
Certain 2-quinoxalinol-4-oxides are selectively reduced to form 2-quinoxalinols employing hydrogen as a reducing agent by reacting such 2-quinoxalinol-4-oxides with a catalyst selected from the group consisting of platinum, rhodium, ruthenium and nickel at between about 20° and about 150°C and at between about 6 and about 60 atmospheres.