Method for continuously producing ketomalonic acid compound using flow reactor

Abstract

The purpose of the present invention is to provide a method for continuously producing a ketomalonic acid compound such as a ketomalonic acid diester or a hydrate thereof, which is an industrially useful compound, on an industrial scale and in a safe and steady manner. The present invention relates to: a method in which a malonic acid diester, a carboxylic acid compound and a chlorous acid compound are used as raw material compounds, and these raw material compounds are mixed together to prepare a mixture and the mixture is supplied to a flow reactor continuously, thereby continuously producing a corresponding ketomalonic acid diester or a hydrate thereof; and a continuous production apparatus for performing the method.

1 . A continuous production apparatus, characterized in that the apparatus comprising:
 (1) a mixing part configured to mix a malonic acid diester, a carboxylic acid compound, and a chlorous acid compound;   (2) a temperature rising part configured to raise the temperature of the mixed mixture thereof; and   (3) a reaction part configured to react the mixture having a temperature raised by the temperature rising part,   which is for continuously producing a corresponding ketomalonic acid diester or a hydrate thereof from the malonic acid diester as a raw material compound,   wherein the temperature rising part of (2) and the reaction part of (3) are one or two or more flow reactors.   
     
     
         2 . The continuous production apparatus according to  claim 1 , wherein the flow reactors are one or two or more tubular flow reactors. 
     
     
         3 . The continuous production apparatus according to  claim 2 , wherein an equivalent diameter of the tubular flow reactors is from 0.5 mm to 50 mm. 
     
     
         4 . The continuous production apparatus according to  claim 1 , wherein the temperature rising part and the reaction part are present in one tubular flow reactor. 
     
     
         5 . The continuous production apparatus according to  claim 1 , wherein the apparatus comprising:
 (4) an aging part configured to further age the reaction mixture obtained in the process of reacting the mixture in addition to the parts of said (1) to (3).   
     
     
         6 . The continuous production apparatus according to  claim 5 , wherein the aging part is one or two or more tubular flow reactors. 
     
     
         7 . The continuous production apparatus according to  claim 1 , wherein the apparatus comprising:
 (5) a quenching part configured to quench a reaction in addition to the parts of said (1) to (3) or said (1) to (4).   
     
     
         8 . The continuous production apparatus according to  claim 7 , wherein the quenching part is one or two or more tubular flow reactors.