反应条件
1: 17α-acetoxy-pregn-4-ene-3,20-dione With methanesulfonic acid; orthoformic acid triethyl ester in ethylene glycol dimethyl ether Heating / reflux; 2: formaldehyd With N-methylaniline in ethylene glycol dimethyl ether T=40°C; Mannich Reaction; 3: With hydrogenchloride in ethylene glycol dimethyl ether; water T=20°C; Hofmann Elimination;
参考文献
ANNEN, Klaus; Linz, Thomas; Neff, Karl-Heinz; Bohlmann, Rolf; Laurent, Henry
Patent: US2009/12321 A1, 2009 ;
Location in patent: Page/Page column 3 ;