Process for the production of 11beta, 17alpha-dihydroxy-4-pregnene-3, 20-dione

Claim 1

A PROCESS FOR THE PRODUCTION OF 11B, 17A-DIHYDROXY-4-PREGNANE-3, 20-DIONE WHICH COMPRISES: MIXING 17A-HYDROXYPREGNANE-3, 11, 20-TRIONE WITH AN ALKANEDIOL CONTAINING FROM TWO TO EIGHT CARBON ATOMS INCLUSIVE, IN THE PRESENCE OF AN ACID CATALYST; REDUCING THE THUS-OBTAINED 17A-HYDROXYPREGNANE-3, 11, 20-TRIONE, 3, 20-CYCLIC DIKETAL WITH A REDUCING AGENT TO A 11B, 17A-DIHYDROXYPREGNANE-3, 20-DIONE, 3, 20-CYCLIC DIKETAL; HYDROLYZING THE THUS-OBTAINED 11B, 17A - DIHYDROXYPREGNANE - 3, 20DIONE, 3, 20-CYCLIC DIKETAL WITH AN ACID TO GIVE 11B, 17ADIHYDROXYPREGNANE-3, 20-DIONE; CONTACTING 11B, 17A-DIHYDROXYPREGNANE-3, 20-DIONE WITH HALOGEN HAVING AN ATOMIC WEIGHT BETWEEN 35 AND 80 TO PRODUCE 4-HALO-11B, 17ADIHYDROXYPREGNANE-3, 20-DIONE; REACTING THE THUS-PRODUCED 4-HALO-11B, 17A-DIHYDROXY-PREGNANE-3, 20-DIONE WITH A HYDRAZINE HAVING A PRIMARY AMINE IN THE HYDRAZINE GROUP TO FORM A 3-HYDRAZONE OF 11B, 17A-DIHYDROXY-4PREGNENE-3, 20-DIONE; AND THEN HYDROLYZING THE THUSPRODUCED 11B, 17A-DIHYDROXY-4-PREGNENE-3, 20-DIONE, 3HYDRAZONE WITH A CARBONYL COMPOUND SELECTED FROM THE GROUP CONSISTING OF ALDEHYDES AND KETONES TO PRODUCE 11B, 17A-DIHYDROXY-4-PREGNENE- 3, 20-DIONE.