Claims
- 1. A process for the production of 1,4-dihydropyridinecarboxylic acid of the formula ##STR22## or its salt, in which
- R is an aryl radical or a heterocyclic radical selected from thienyl, furyl, pyrryl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, pyridyl, pyridazinyl, pyrimidyl, pyrazinyl, quinolyl, isoquinolyl, indolyl, benzimidazolyl, quinazolyl and quinoxalyl, in which the aryl radical or the heterocyclic radical optionally contains 1 to 3 identical or different substituents selected from phenyl, alkyl, alkenyl, alkinyl, alkoxy, halogen, trifluoromethyl, trifluoromethoxy, alkylamino, nitro, cyano, azido, carboxamido, sulphonamido and SO.sub.m --alkyl (in which m is 0, 1 or 2)
- R.sup.1 and R.sup.2 are identical or different and denote a hydrogen atom, a straight-chain or branched alkyl radical, an aryl radical or an aralkyl radical and
- X (a) is a --COOH group or
- (b) is a group of the formula --COR.sup.3,
- in which
- R.sup.3 is an optionally substituted alkyl, aryl, aralkyl, amino, monoalkylamino or dialkylamino group,
- or
- (c) is a group of the formula --COOR.sup.4
- in which
- R.sup.4 is a straight-chain, branched or cyclic, saturated or unsaturated hydrocarbon radical which is optionally interrupted by an oxygen or a sulphur atom or by an --SO-- or --SO.sub.2 --group in the chain, and/or which is optionally substituted by one halogen or by 1 or 2 trifluoromethyl groups or by one phenyl, phenoxy, phenylthio or phenylsulphonyl group, which in turn is optionally substituted by halogen, cyano, dialkylamino, alkoxy, alkyl, trifluoromethyl or nitro, or in which the hydrocarbon radical is optionally substituted by pyridyl or amino, these amino groups carrying two identical or different substituents selected from alkyl, alkoxyalkyl, aryl and aralkyl, and these substituents optionally form, with the nitrogen atom, a 5- to 7-membered ring which optionally contains an oxygen or sulphur atom or the N-alkyl grouping as a further hetero-atom, or
- (d) is a group of the formula --S(O).sub.r --R.sup.5
- in which
- r.sub.5 is 0, 1 or 2 and
- R.sup.5 denotes a straight-chain, branched or cyclic saturated or unsaturated aliphatic hydrocarbon radical, optionally interrupted by an oxygen atom in the chain and/or which is optionally substituted by amino or an aryl radical selected from phenyl, phenoxy, phenylthio, phenylsulphonyl, and pyridinyl, the aryl radicals being optionally substituted by halogen, cyano, dialkylamino, alkoxy, alkyl, trifluoromethyl and nitro, and the amino group being optionally substituted by 2 identical or different substituents selected from alkyl, alkoxyalkyl, aryl or aralkyl, these substituents optionally form, with the nitrogen atom, a 5- to 7-membered ring which optionally contains an oxygen or sulphur atom or the N-alkyl grouping as a further hetero-atom,
- or in which
- R.sup.5 is an aryl radical which optionally contains 1 to 3 identical or different substituents selected from alkyl, alkoxy, halogen, cyano, trifluoromethyl, trifluoromethoxy, dialkylamino and nitro, which comprises hydrolyzing a 1,4-dihydropyridine derivative of the formula ##STR23## in which R, R.sup.1, R.sup.2 and X have the above-mentioned meaning,
- n is 1, 2, 3 or 4 and
- Y denotes an electron-attracting group under alkaline conditions in the presence of an inert organic solvent in a temperature range from 10.degree. to 100.degree. C.
- 2. A process according to claim 1 in which R, R.sup.1, R.sup.2, X, n and Y have the same meanings as in claim 1 with the proviso that the heterocyclic radical of R is substituted by 1 to 3 identical or different substituents selected from those specified in claim 1.
- 3. A process according to claim 1 for the preparation of a compound of the formula (I) or its salt,
- in which
- R is a pyridyl radical or a phenyl radical which contains one or two identical or different substituents selected from halogen, nitro, cyano, trifluoromethyl, azido, trifluoromethoxy or alkoxy with 1 or 2 carbon atoms,
- R.sup.1 and R.sup.2 are identical or different and denote a hydrogen atom, an alkyl group with 1 or 2 carbon atoms, a phenyl radical or a benzyl radical and
- X (a) is the group --COOH
- or
- (b) is the group --COR.sup.3,
- in which
- R.sup.3 is an alkyl group with 1 to 4 carbon atoms,
- or
- (c) is the group --COOR.sup.4,
- in which
- R.sup.4 is a straight-chain, branched or cyclic, saturated or unsaturated hydrocarbon radical, which is optionally interrupted in the chain by an oxygen or sulphur atom or by the --SO.sub.2 --group, or denotes a benzyl radical,
- or
- (d) is the group --SO.sub.2 --R.sup.5,
- in which
- R.sup.5 is a straight-chain or branched, saturated or unsaturated hydrocarbon radical with up to 6 carbon atoms, or a phenyl radical.
- 4. A process according to claim 1, in which the substituent Y in the formula (II) denotes a chlorine atom, a cyano group or an acetoxy group and n is 2.
- 5. A process according to claim 1, in which the hydrolysis is carried out in the presence of alkali metal hydroxides in a temperature range from 20.degree. to 50.degree. C.
- 6. A process according to claim 1, in which the solvent is an aliphatic alcohol with 1 to 4 carbon atoms or 1,2-dimethoxyethane.
- 7. A process according to claims 2 or 3 in which the hydrolysis is carried out in the presence of an alkali metal hydroxide.
- 8. A process according to any of claims 2 or 3 in which the hydrolysis is carried out in a temperature range from 20.degree. to 50.degree. C.
- 9. A process according to any of claims 2 or 3 in which the solvent is an aliphatic alcohol with 1 to 4 carbon atoms or 1,2-dimethoxyethane.
- 10. A process according to claim 1 for the production of a dihydropyridinediester of a compound of formula (I) as defined in claim 1 in which X is a radical (c) which comprises esterifying the free carboxylic acid group of that compound of formula (I) in which X denotes a radical (c).
Parent Case Info
This is a division of application Ser. No. 084,338, filed Oct. 12, 1979 now U.S. Pat. No. 4,285,955 issued Aug. 25, 1981.
Non-Patent Literature Citations (1)
Entry |
Noller, Textbook of Organic Chemistry, 2nd Edition, W. B. Saunders Company, Philadelphia, 1958. |
Divisions (1)
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Number |
Date |
Country |
Parent |
84338 |
Oct 1979 |
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