تفاعل #55608
ord-b01cfadabc644815ab56cb9b5069bf1c
معادلة التفاعل
المتفاعلات
الكواشف
ظروف التفاعل
المعالجة
- 1أخرىthe following Oppenhauer reaction
الإجراء التجريبي
A preferred process for preparing 17β-N,N-diethylcarbamoyl-4-methyl-4-aza-5α-androstan-3-one, an especially preferred compound of the present invention, comprises the following steps: (a) pregnenolone (V), an available starting material, is treated by the haloform King reaction with iodine and pyridine to form the 20-pyridinum iodide derivative of the pregnenolone (VI); (b) the pyridinium iodide derivative (VI) is methanolyzed to the methyl ester of 17-carboxy androstenol (VII) with sodium methoxide and methanol, the ester form being preferred for carrying out the following Oppenhauer reaction; (c) the methyl ester of 17-carboxy androstenol (VII) is treated with aluminum isopropoxide and cyclohexanone in an appropriate solvent such as toluene to yield methyl-4-androstene-3-one-17-carboxylate (VIII) (d) the methyl-4-androstene-3-one-17-carboxylate (VIII) thus formed is hydrolyzed to the 17-acid (IX) under acid conditions in a methanol: water solvent of approximately 4:1 proportions; (e) the 17 acid (IX) is then treated with an oxalyl chloride: pyridine complex of approximately 1:1 proportions in toluene or other suitable solvent, e.g. xylene, to form the 17 -acid chloride (X); (f) the 17-acid chloride (X) is then treated in situ with an excess of diethylamine to form the 17β-N,N-diethylcarbamoyl-4-androstene-3-one (XI); (g) the 4-androstene-3-one (XI) thus formed is oxidized by treatment with sodium periodate and potassium permanganate, using tert-butanol and water as a solvent system, to the corresponding 5-oxo-3,5-secoandrostan-3-oic acid (XII); (h) the secoandrostanoic acid (XII) is then converted to the corresponding 4-aza compound (XIII) by treating it with methylamine in ethylene glycol for a period of about 1 hour over which time the reaction mixture temperature is raised to from 140°-180° C. where it is maintained from 0.5 to 5 minutes; (i) the resulting 17β-N,N-diethylcarbamoyl-4-methyl-4-aza-5-androsten-3-one (XIII) is then hydrogenated by treating it with hydrogen at room temperature to 60° C. or higher, using platinum oxide as the catalyst, to form the 17β-N,N-diethylcarbamoyl-4-methyl-4-aza-5α-androstan-3-one (XIV) final product, which is then separated and purified.