Preparation of carboxylic chlorides

• US 5,200,560 A
• Filed: 06/30/1992
• Issued: 04/06/1993
• Est. Priority Date: 04/21/1990
• Status: Expired due to Term

• Current Assignee: BASF AG (BASF SE)
• Original Assignee: BASF AG (BASF SE)
• Inventors: Henkelmann, Jochem, Schwarz, Wolfgang, Franzischka, Wolfgang, Hupfer, Leopold, Kahl, Thomas M.
• Primary Examiner(s): Killos, Paul J.
• Application Number:
  US07/908,439
• Time in Patent Office: 280 Days
• Field of Search: 562/857
• US Class Current: 562/857
• CPC Class Codes: C07C 51/60 by conversion of carboxylic acids or their anhydrides or esters, lactones, salts into halides with the same carboxylic acid part

Abstract

A process for the preparation of a carboxylic chloride of the general formula I ##STR1## in which R denotes C₁ -C₃₀ -alkyl, C₂ -C₃₀ -alkenyl or C₂ -C₃₀ -alkynyl, from a carboxylic acid of the general formula II ##STR2## in which R has the meanings stated, and phosgene COCl₂ (III), in the presence of a catalyst adduct comprising phosgene and N,N-disubstituted formamide of the general formula IV ##STR3## in which R¹ and R² are independently C₁ -C₃ -alkyl or R¹ and R² together form a C₄ - or C₅ -alkylene chain which may or may not be interrupted by an oxygen atom or by a nitrogen atom carrying a C₁ -C₃ -alkyl group or CHO, the product being isolated by phase separation, wherein the amount of phosgene added to the formamide (IV) is from 20 to 70% molar, based on the formamide.

Claims

1. In a process for the preparation of a carboxylic chloride of the formula ##STR7## in which R denotes C₁ -C₃₀ -alkyl, C₂ -C₃₀ -alkenyl or C₂ -C₃₀ -alkynyl, by reacting a carboxylic acid of the formula ##STR8## in which R has the meanings stated with liquid or gaseous phosgene ##STR9## in the presence of a catalyst adduct of phosgene and N,N-disubstituted formamide of the formula ##STR10## in which R¹ and R² are independently C₁ -C₃ -alkyl or R¹ and R² together form a C₄ - or C₅ -alkylene chain which may or may not be interrupted by an oxygen atom or by a nitrogen atom carrying a C₁ -C₃ -alkyl group or CHO, the product (I) being isolated from the catalyst adduct by phase separation, the improvement which comprises:

carrying out the reaction in the presence of said catalyst adduct of phosgene and N,N-disubstituted formamide (IV) in which the amount of phosgene in the adduct is kept between about 20 to 70% molar, based on the formamide.

2. A process as claimed in claim 1, wherein the reaction is carried out continuously.

3. A process as claimed in claim 1, wherein the amount of phosgene in the catalyst adduct is kept between about 30 to 60% molar, based on the formamide.

4. A process as claimed in claim 1, wherein the amount of phosgene in the catalyst adduct is kept between about 40 to 50% molar, based on the formamide.

5. A process as claimed in claim 1, wherein the carboxylic acid reactant (I) is an aliphatic monocarboxylic acid of from 1 to 30 carbon atoms.

6. A process as claimed in claim 1, wherein the carboxylic acid reactant (I) is an aliphatic monocarboxylic acid of from 1 to 20 carbon atoms.

7. A process as claimed in claim 1, wherein the reaction of the carboxylic acid (II) and the phosgene (III) is carried out at a temperature between 20°

and 100°

C.

8. A process as claimed in claim 1, wherein the reaction of the carboxylic acid (II) and the phosgene (III) is carried out at a temperature between 30°

and 80°

C.

9. A process as claimed in claim 1, wherein the reaction of the carboxylic acid (II) and the phosgene (III) is carried out at a temperature between 40°

and 70°

C.

10. A process as claimed in claim 1, wherein the catalyst adduct of phosgene and the N,N-disubstituted formamide (IV) is used in an amount of from 5 to 200% molar, based on the carboxylic acid reactant (II).

11. A process as claimed in claim 1, wherein the catalyst adduct of phosgene and the N,N-disubstituted formamide (IV) is used in an amount of from 10 to 100% molar, based on the carboxylic acid reactant (II).

12. A process as claimed in claim 1, wherein the catalyst adduct of phosgene and the N,N-disubstituted formamide (IV) is used in an amount of from 10 to 30% molar, based on the carboxylic acid reactant (II).

13. A process as claimed in claim 1, wherein the formamide (IV) in the catalyst adduct is selected from the group consisting of dimethyl formamide and diethyl formamide.