Title:
A PROCESS FOR THE PREPARATION OF 2,2-DIMETHYL-5-(4-CHLOROBENZYL) CYCLOPENTANONE AND AN INTERMEDIATE USEFUL THEREFOR
Document Type and Number:
WIPO Patent Application WO2002000608
Kind Code:
A3
Abstract:
A process for the preparation of 2,2-dimethyl-5-(4-chlorobenzyl)cyclopentanone (I) by reaction isobutyronitrile with 1-bromo-3-chloropropane in the presence of a first base in a non-polar solvent to afford 5-chloro-2,2-dimethylpentanenitrile; treating said 5-chloro-2,2-dimethylpentanenitrile with a cyanide-delivering reagent in the presence of a phase-transfer catalyst to form 2,2-dimethyladiponitrile; cyclizing said 2,2-dimethyladiponitrile in the presence of a second base in a non-polar solvent to afford 3,3-dimethyl-2-amino-1-cyanocyclopentene; hydrolyzing said 3,3-dimethyl-2-amino-1-cyanocyclopentene in the presence of an acid to give 5-cyano-2,2-dimethylcyclopentanone; treating said 5-cyano-2,2-dimethylcyclopentanone with 4-chlorobenzyl chloride in the presence of a third base in a polar aprotic solvent to form 5-(4-chorobenzyl)-5-cyano-2,2-dimethylcyclopentanone; and hydrolyzing said 5-(4-chlorobenzyl)-5-cyano-2,2-dimethylcyclopentanone in the presence of an acid to give the desired 5-(4-chlorobenzyl)-2,2-dimethylcyclopentanone; the compound, 5-(4-chlorobenzyl)-5-cyano-2,2-dimethylcyclopentanone.
Inventors:
WONG GEORGE S K
Application Number:
PCT/EP2001/006578
Publication Date:
May 30, 2002
Filing Date:
June 11, 2001
Export Citation:
Assignee:
BASF AG (DE)
International Classes:
C07B61/00; C07C45/67; C07C49/697; C07C253/30; C07C45/65; C07C255/04; C07C255/10; C07C255/46; (IPC1-7): C07C255/46; C07C49/697; C07C45/67; C07C253/00
Foreign References:
| EP0267778A2 | 1988-05-18 |
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