Ammonium Chloride → 21-Ethyl-3alpha-hydroxy-5alpha-pregnane-11,20-dione

HRID 1973736Notes

Reaction equation

HRID 1973736 reaction equation
[CH3:1][Li].[OH:3][C@@H:4]1[CH2:24][CH2:23][C@@:22]2([CH3:25])[C@@H:6]([CH2:7][CH2:8][C@@H:9]3[C@@H:21]2[C:20](=[O:26])[CH2:19][C@@:18]2([CH3:27])[C@H:10]3[CH2:11][CH2:12][C@@H:13]2[C:14](=[O:17])[CH:15]=[CH2:16])[CH2:5]1.[Cl-].[NH4+]>CCOCC>[CH2:16]([CH2:15][C:14](=[O:17])[C@@H:13]1[C@:18]2([CH3:27])[C@H:10]([C@H:9]3[C@H:21]([C:20](=[O:26])[CH2:19]2)[C@:22]2([CH3:25])[C@H:6]([CH2:5][C@H:4]([OH:3])[CH2:24][CH2:23]2)[CH2:7][CH2:8]3)[CH2:11][CH2:12]1)[CH3:1]

Participants

5

Reactant 3

HCID 25517Ammonium ChlorideHCID 86734286HCID 86734286, compoundHCID 178418348HCID 178418348, compound

Product 1

HCID 8673430821-Ethyl-3alpha-hydroxy-5alpha-pregnane-11,20-dione

Reagents, catalysts & solvents 1

HCID 3283Diethyl EtherSolvent4×

Procedure

Methyl lithium in ether (≈1.3M: 7.5 ml) was added slowly to a slurry of cuprous iodide (950 mg) in dry ether (40 ml) under nitrogen at -20°, the initial yellow precipitate just redissolving. 3α-Hydroxy-21-methylene-5α-pregnane-11,20-dione (500 mg) in dry ether (10 ml) was added rapidly to the solution forming a yellow precipitate. After 3/4 hr. at ≈0° the mixture was poured into saturated ammonium chloride solution and the oily precipitate extracted with ether. The extracts were washed with saturated ammonium chloride solution, then water, and dried over anhydrous sodium sulphate. The dried solution was evaporated to an off white foam (430 mg) which was purified by preparative t.l.c. in ethyl acetate/petrol (1:1). The main band (Rf ≈ 0.4) gave a white foam which on trituration with petrol, containing a small quantity of ether, gave title compound (320 mg.) as a white solid, m.p. 112°-113°, [α]D + 105° (c = 1.01).

Workup

  1. dissolutionthe initial yellow precipitate just redissolving
  2. customforming a yellow precipitate
  3. waitAfter 3/4 hr
  4. extractionthe oily precipitate extracted with ether
  5. washThe extracts were washed with saturated ammonium chloride solution
  6. dry with materialwater, and dried over anhydrous sodium sulphate
  7. customThe dried solution was evaporated to an off white foam (430 mg) which
  8. customwas purified by preparative t.l.c
  9. customThe main band (Rf ≈ 0.4) gave a white foam which on trituration with petrol

Sources & evidence

ORD record
ord-20f8fc7da8544dd79437e9ea1e31f9b6
Source dataset
uspto-grants-1976_12
Patent number
US03998829

Reaction notes

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