Process for the production of 4-alkoxyacetoacetic acid esters

Claim 2

Process for the production of a 4-alkoxyacetoacetic acid ester from a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester consisting of reacting a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester with more than one equivalent of an alkali alcoholate in at least one aprotic solvent at a temperature of 50° to 100° C., whereby the 4-alkoxyacetoacetic acid ester results, the 4-alkoxyacetoacetic acid ester having the formula: ##STR2## wherein R and R 2 are each alkyl, and R 1 is H, alkyl or substituted alkyl.

Claim 3

Process as claimed in claim 1 wherein the aprotic solvent is acetonitrile or propionitrile.

Claim 4

Process as claimed in claim 1 wherein at least 2.0 moles of the alkali alcoholate are used per mole of the 4-chloroacetoacetic ester or 4-bromoacetoacetic ester.

Claim 5

Process as claimed in claim 1 wherein the reaction is operated at a temperature of 60° to 80° C.

Claim 6

Process as claimed in claim 1 wherein R 1 is alkyl substituted with methoxy or aryl.

Claim 7

Process as claimed in claim 1 wherein R 1 is an alkyl group, having 1 to 12 carbon atoms, substituted with methoxy, benzyl or naphthyl.

Claim 8

Process as claimed in claim 1 wherein 2 to 10 moles of the alkali alcoholate are used per mole of the 4-chloroacetoacetic ester or 4-bromoacetoacetic ester.

Claim 9

Process as claimed in claim 1 wherein R is an alkyl group having 1 to 12 carbon atoms, R 1 is an alkyl group having 1 to 12 carbon atoms and R 3 is an alkyl group having 1 to 12 carbon atoms.

Claim 10

Process as claimed in claim 1 wherein the alkali metal in the alkali alcoholate is sodium or potassium and the alcohol component of the alkali alcoholate is an aliphatic alcohol having 1 to 10 carbon atoms.

Claim 11

Process as claimed in claim 1 wherein the aprotic solvent has a relative donor number which is above 11.

Claim 12

Process as claimed in claim 1 wherein the reaction is carried out over a time period of 20 to 40 minutes.

Claim 13

Process as claimed in claim 1 wherein one aprotic solvent is present.

Claim 14

Process for the production of a 4-alkoxyacetoacetic acid ester from a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester consisting of (a) reacting a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester with more than one equivalent of at least one alkali alcoholate in at least one aprotic solvent at a temperature of 50° to 100° C., whereby the 4-alkoxyacetoacetic acid ester results, the 4-alkoxyacetoacetic acid ester has the formula: ##STR3## wherein R and R 2 are each alkyl, and R 1 is H, alkyl or substituted alkyl, and (b) separating the 4-alkoxyacetoacetic acid ester from reaction mixture (a).

Claim 15

Process for the production of a 4-alkoxyacetoacetic acid ester from a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester consisting of (a) reacting a 4-chloroacetoacetic ester or a 4-bromoacetoacetic ester with more than one equivalent of at least one alkali alcoholate in at least one aprotic solvent at a temperature of 50° to 100° C., whereby the 4-alkoxyacetoacetic acid ester results, the 4-alkoxyacetoacetic acid ester has the formula: ##STR3## wherein R and R 2 are each alkyl, and R 1 is H, alkyl or substituted alkyl, and (b) separating the 4-alkoxyacetoacetic acid ester from reaction mixture (a).

Claim 16

Process as claimed in claim 13 wherein separation (b) comprises: (i) introducing separately and simultaneously reaction mixture (a) and hydrochloric acid into a solution of acetic acid and water, solution (i) being cooled, the amount of water present in solution (i) being sufficient to prevent precipitation of NaCl, but not so large that a phase separation is prevented, sufficient hydrochloric acid being added to maintain solution (i) at a pH between 4.5 and 8; (ii) allowing the neutralized solution (i) to stand until phases are formed; (iii) separating the aqueous phase and combining the remaining two organic phases; and (iv) removing the 4-alkoxyacetoacetic acid ester from the organic phases by distillation.