PURPOSE: To easily produce a 2,4-dioxyquinoline derivative useful as an intermediate for pharmaceuticals and agricultural chemicals, etc., in high yield and selectivity with a one-step reaction, by cyclizing an arylmalonic acid amide ester derivative with a polyphosphoric acid.
CONSTITUTION: The objective compound of formula II, e.g. 7,8-dimethyl-2,4- dioxyquinoline useful as an intermediate for a remedy for allergic asthma can be produced at a low cost by cyclizing an arylmalonic acid amide ester derivative of formula I (R1WR4 are H, lower alkyl, lower alkoxy or halogen; R5 is lower alkyl) at 50W200°C, preferably 100W150°C using a polyphosphoric acid prepared at a P2O3/H2PO4 ratio of 0.2W2.0, preferably 0.4W0.6. The amount of the polyphosphoric acid is 0.1W50ml, preferably 0.2W20ml per 1.0g of the compound of formula I.
TAKUMA ISAKI
OOISHI MARI
| JPS5030884A | 1975-03-27 | |||
| JPS4993375A | 1974-09-05 |
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