US 20020165414Al  May 17, 2000  (DE) ..................................... 100 24 264.2  Process for the production of 2,2,6-trimethylcyclohexane-l,  4-dione by epoxidation of ~-isophorone with organic per› carboxylic acids at a water content below 5 wt.-% and  subsequent isomerization of the mixture of ~-isophorone  epoxide and hydroxyisophorone.  (57)  ABSTRACT  Publication Classification  (30)  Foreign Application Priority Data  Related U.S. Application Data  (19)  United States  (12)  Patent Application Publication  Krill et al.  (10)  Pub. No.: US 2002/0165414 Al  ( 43)  Pub. Date:  Nov. 7, 2002  (62)  Division of application No. 09/850,156, filed on May  8, 2001.  (51)  Int. Cl.7  .....................................................  C07C 45/27  (52)  U.S. Cl.  ..............................................................  568/343  (21)  Appl. No.:  10/084,157  (22)  Filed:  Feb.28,2002  (76)  Inventors:  Steffen  Krill,  Speyer (DE);  Klaus  Huthmacher,  Gelnhausen (DE);  Sylvain Perrin,  Gueugnon (FR)  (54)  PROCESS FOR THE PRODUCTION OF  2,2,6-TRIMETHYLCYCLOHEXANE-1,  4-DIONE  Correspondence Address:  SMITH, GAMBRELL  &  RUSSELL, LLP  1850 M STREET, N.W., SUITE 800  WASHINGTON, DC 20036 (US) 