α-chloronitriles production method

• US 6,353,127 B1
• Filed: 04/25/2001
• Issued: 03/05/2002
• Est. Priority Date: 11/04/1998
• Status: Expired due to Fees

• Current Assignee: BASF AG (BASF SE)
• Original Assignee: BASF AG (BASF SE)
• Inventors: Henkelmann, Jochem, Stamm, Armin, Siegel, Wolfgang, Fischer, Jakob
• Primary Examiner(s): McKane, Joseph K.
• Assistant Examiner(s): MURRAY, JOSEPH H
• Application Number:
  US09/830,349
• Time in Patent Office: 314 Days
• Field of Search: 558/460
• US Class Current: 558/460
• CPC Class Codes: C07C 253/30 by reactions not involving the formation of cyano groups
• CPC Class Codes: C07C 255/10 containing cyano groups and halogen atoms, or nitro or nitroso groups, bound to the same acyclic carbon skeleton
• CPC Class Codes: C07C 255/35 the carbon skeleton being further substituted by halogen atoms, or by nitro or nitroso groups

Abstract

The invention relates to a process for the preparation of α-chloronitriles by reaction of cyanohydrins of aldehydes or ketones with phosgene using a phosphine oxide as catalyst.

Claims

1. A process for the preparation of α

-chloronitriles by reaction of cyanohydrins of aldehydes or ketones with phosgene using a catalyst, wherein the catalyst is a phosphine oxide.

2. A process as claimed in claim 1, wherein the catalyst used is a mixture of C₆-C₈-tri-alkylphosphine oxides.

3. A process as claimed in claim 1, wherein the catalyst is used in an amount of from 0.5 to 5 mol %, based on the cyanohydrin used.

4. A process as claimed in claim 1, wherein the cyanohydrins used are prepared by reaction of aldehydes or ketones with hydrogen cyanide, and the resulting reaction mixture is reacted directly with phosgene without prior isolation.

5. A process as claimed in claim 1, wherein the reaction is carried out in an inert organic solvent.

6. A process as claimed in claim 5, wherein the α

-chloronitrile to be produced is used as solvent.

7. A process as claimed in claim 1, wherein the reaction is carried out at temperatures of from 50 to 150°

C.