GB1289020A - - Google Patents

Abstract

1289020 Halopregnenes F HOFFMANN-LA ROCHE & CO AG 10 Dec 1970 [11 Dec 1969 (2)] 58718/70 Heading C2U The invention comprises (A) compounds of Formulµ III and IV (wherein R 1 , R 2 and R 4 are each Cl or Br and n is 0, 1, 2, 3, 4 or 5); and (B) a process for preparing compounds of Formula I (wherein R 3 is C 1-6 straight-chained alkylidene) from compounds of Formula II by converting the latter, either directly or via compounds of Formula IV, into compounds of Formula III which are then refluxed in an inert organic solvent with an alkali metal iodide in the presence of, or followed by the addition of, a C 1-6 alkenoic acid, to give the compounds of Formula I. The conversion of II to IV is effected with Cl 2 or Br 2 . The conversion of IV to III is effected with a dehydrohalogenating agent, and the direct conversion of II to III is effected with Cl 2 , or Br 2 in the presence of a dehydrohalogenating agent. 6 - Chloro - 16# - chloromethyl - 16α,17α- epoxypregna - 4,6 - diene - 3,20 - dione (VI) is prepared from 3# - acetoxy - 17α - hydroxy- 16 - methylenepregn - 5 - en - 20 - one (V) by the sequence: V # 3# - acetoxy - 5α,6#- dichloro 16# - chloromethyl - 16α,17α - epoxypregnan - 20 - one # 3# - hydroxy - 5α,6#- dichloro - 16# - chloromethyl - 16α,17α - epoxypregnan - 20 - one # 5α,6# - dichloro - 16#- chloromethyl - 16α,17α - epoxypregnane - 3,20- dione # 6# - chloro - 16# - chloromethyl- 16α,17α - epoxypregn - 4 - ene - 3,20 - dione # 3 - ethoxy - 6 - chloro - 16# - chloromethyl- 16α,17α - epoxypregna - 3,5 - dien - 20 - one # VI.