US4723011A
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Preparation of substituted and disubstituted-pyridine-2,3-dicarboxylate esters
Assignee: Wyeth Holdings LLC
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Filing: 1985-10-28
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Granted: 1988-02-02
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Expires: 2005-10-28
Abstract
Abstract Pyridine-2,3-dicarboxylates of Formula I ##STR1## are prepared by reacting an alpha halo-beta keto ester of formula II ##STR2## with an alpha, beta-unsaturated aldehyde or ketone of formula III ##STR3## in the presence of a minimum of 2 molar equivalents of ammonium salt.
Inventors
- 👤 Robert F. Doehner, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:49
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/04; C07D213/24; C07D213/54; C07D213/55; C07D213/60; C07D213/78; C07D213/79; C07D213/80
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
144 words
A method for the preparation of substituted and disubstituted pyridine-2,3-dicarboxylates of formula I ##STR18## wherein R 3 is hydrogen, halogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; R 4 and R 7 are each hydrogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; and R 5 and R 6 are each C 1 -C 4 alkyl; comprising reacting an α-halo-β-ketoester of formula II ##STR19## wherein R 5 and R 6 are defined above with an α,β-unsaturated aldehyde or ketone of formula III ##STR20## wherein R 3 , R 4 and R 7 are as described in formula I in the presence of a minimum of 2 molar equivalents of an ammonium salt in a solvent in a temperature range of ambient temperature to the boiling point of the solvent until the reaction is essentially complete.
Claim 2
Independent Claim
144 words
A method for the preparation of substituted and disubstituted pyridine-2,3-dicarboxylates of formula I ##STR18## wherein R 3 is hydrogen, halogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; R 4 and R 7 are each hydrogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; and R 5 and R 6 are each C 1 -C 4 alkyl; comprising reacting an α-halo-β-ketoester of formula II ##STR19## wherein R 5 and R 6 are defined above with an α,β-unsaturated aldehyde or ketone of formula III ##STR20## wherein R 3 , R 4 and R 7 are as described in formula I in the presence of a minimum of 2 molar equivalents of an ammonium salt in a solvent in a temperature range of ambient temperature to the boiling point of the solvent until the reaction is essentially complete.
Claim 3
Dependent Claim
28 words
A method according to claim 1 wherein the solvent is water, an alcohol, hydrocarbon, chlorinated hydrocarbon, aromatic hydrocarbon, ether, organic acid or ester, dimethyl sulfoxide, dimethylformamide, or acetonitrile.
Claim 4
Dependent Claim
21 words
A method according to claim 2 wherein the reaction is conducted in a temperature range of 30° C. to 140° C.
Claim 5
Dependent Claim
14 words
A method according to claim 3 wherein the formula II compound is diethyl 3-chloro-2-oxo-butanedioate.
Claim 6
Dependent Claim
15 words
A method according to claim 3 for the preparation of 5-substituted, 6-substituted and 5,6-disubstituted pyridine-2,3-dicarboxylates.
Claim 7
Dependent Claim
12 words
A method according to claim 3 for the preparation of diethyl 5-ethylpyridine-2,3-dicarboxylate.
Claim 8
Dependent Claim
12 words
A method according to claim 3 for the preparation of diethyl 5-methylpyridine-2,3-dicarboxylate.
Claim 9
Dependent Claim
12 words
A method according to claim 3 for the preparation of diethyl 5,6-dimethylpyridine-2,3-dicarboxylate.
Claim 10
Dependent Claim
12 words
A method according to claim 3 for the preparation of diethyl pyridine-2,3-dicarboxylate.
Claim 11
Independent Claim
143 words
A method for the preparation of substituted nicotinates having the structure ##STR21## wherein R 3 is hydrogen, halogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; R 4 and R 7 are each hydrogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, substituted-phenyl; R 6 and R 8 are each C 1 -C 4 alkyl; comprising reacting an α-halo-β-ketoester of formula V ##STR22## wherein R 6 and R 8 are as defined for formula IV, with an α,β-unsaturated aldehyde or ketone of formula III ##STR23## wherein R 3 , R 4 and R 7 are as described in formula IV, in the presence of a minimum of 2 molar equivalents of an ammonium salt in a solvent in a temperature range of ambient temperature to the boiling point of the solvent until the reaction is essentially complete.
Claim 12
Independent Claim
143 words
A method for the preparation of substituted nicotinates having the structure ##STR21## wherein R 3 is hydrogen, halogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, or substituted-phenyl; R 4 and R 7 are each hydrogen, C 1 -C 6 straight or branched alkyl, alkenyl, phenyl, substituted-phenyl; R 6 and R 8 are each C 1 -C 4 alkyl; comprising reacting an α-halo-β-ketoester of formula V ##STR22## wherein R 6 and R 8 are as defined for formula IV, with an α,β-unsaturated aldehyde or ketone of formula III ##STR23## wherein R 3 , R 4 and R 7 are as described in formula IV, in the presence of a minimum of 2 molar equivalents of an ammonium salt in a solvent in a temperature range of ambient temperature to the boiling point of the solvent until the reaction is essentially complete.
Claim 13
Dependent Claim
12 words
A method according to claim 10 for the preparation of ethyl 5-ethyl-2-methylnicotinate.
Claim 14
Dependent Claim
12 words
A method according to claim 10 for the preparation of ethyl 2,5-dimethylnicotinate.
References Cited (Backward Citations)
DE2453305A1
Cited
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