Yield:122914-94-7 83%

Reaction Conditions:

with hydrazine hydrate;hydrazinium sulfate in ethanol;water at 20; for 12 h;Inert atmosphere;

Steps:

5A

Example 5Preparation of synthetic intermediate Compound (4)(4a)[00455] 3P-Acetoxyandrost-5-en-17-one (2a) ( (1 g, 3.3 mmol) was dissolved in ethanol (15 mL), and the resulting solution was treated with hydrazine hydrate (~ 80%, 750 μ, 12 mmol) followed by a solution of hydrazine sulfate (2 mg, 15 μιηο) in 70 μ_^ of water. The mixture was stirred under N₂ at room temperature for 12 hours and then poured into ice water. The resulting precipitate was filtered, washed with water and dried to give compound (4a) (0.87 g, yield 83%). MS calculated for (C₂₁H₃₂N₂0₂)⁺ 345.5. 1HNMR (CDC1₃, 300 MHz) major characteristic peaks: δ 5.4 (1H, d), 4.6 (1H, m), 2.0 (3H, s), 1.0 (3H, s), 0.92 (3H, s).

References:

WO2012/83112,2012,A2 Location in patent:Page/Page column 182