Claims
- 1. A process for production of 2-amino-4-hydroxyquinolines having the formula ##STR8## wherein each of R.sub.1, R.sub.2 and R.sub.3 is selected from the group consisting of hydrogen, alkyl having from 1 to 4 carbon atoms, alkoxy having from 1 to 4 carbon atoms, chloro, bromo, fluoro, hydroxy, methylthio and methylsulfinyl, and R.sub.2 and R.sub.3 when taken together are selected from the group consisting of 1,3-butadienyl and alkylenedioxy having from 1 to 2 carbon atoms; which comprises the steps of
- (a) reacting an isatoic anhydride of the formula ##STR9## wherein R.sub.1, R.sub.2 and R.sub.3 are as defined above, in a reaction-inert solvent with malononitrile in the presence of a base selected from the group consisting of trialkylamines having from 3 to 12 carbon atoms, N,N-dimethylaniline, N-methylmorpholine, alkali metal amides, alkali metal alkoxides, alkali metal hydrides, alkali metal hydroxides, triphenylmethyl sodium, sodium and potassium, at a temperature of from about 20.degree. C. to about 150.degree. C.; and
- (b) treating the reaction product of step (a) with (i) a strong acid selected from the group consisting of hydrobromic acid, hydrobromic acid-acetic acid, hydrochloric acid and sulfuric acid, or (ii) a strong base selected from the group consisting of sodium hydroxide and potassium hydroxide at a temperature of from about 80.degree. C. to about 150.degree. C.
- 2. A process according to claim 1 wherein each of R.sub.1, R.sub.2 and R.sub.3 is hydrogen.
- 3. A process according to claim 1 wherein R.sub.1 is alkoxy and each of R.sub.2 and R.sub.3 is hydrogen.
- 4. A process according to claim 1 wherein R.sub.1 is methyl and each of R.sub.2 and R.sub.3 is hydrogen.
- 5. The process according to claim 2 wherein step (a) is conducted in the presence of triethylamine as base and the strong acid of step (b) is hydrobromic acid.
- 6. The process according to claim 3 wherein R.sub.1 is 6-methoxy and triethylamine is used as base in step (a) and step (b) is conducted in the presence of the strong base potassium hydroxide.
CROSS REFERENCE TO RELATED APPLICATION
This application is a division of U.S. application Ser. No. 890,738, filed Mar. 27, 1978, and a continuation-in-part of U.S. application Ser. No. 759,295, filed Jan. 14, 1977 and now abandoned.
US Referenced Citations (2)
Non-Patent Literature Citations (1)
Entry |
Coppola et al., "J. Org. Chem.", vol. 41, 1976, pp. 825-831. |
Divisions (1)
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Number |
Date |
Country |
Parent |
890738 |
Mar 1978 |
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