Diethyl Ether → 3alpha-Nicotinoyloxy-5alpha-pregnan-20-one

HRID 232804

Reaction equation

HRID 232804 reaction equation
[OH:1][C@@H:2]1[CH2:21][CH2:20][C@@:19]2([CH3:22])[C@@H:4]([CH2:5][CH2:6][C@@H:7]3[C@@H:18]2[CH2:17][CH2:16][C@@:15]2([CH3:23])[C@H:8]3[CH2:9][CH2:10][C@@H:11]2[C:12](=[O:14])[CH3:13])[CH2:3]1.Cl.[C:25](Cl)(=[O:32])[C:26]1[CH:31]=[CH:30][CH:29]=[N:28][CH:27]=1.CCOCC>CN(C)C1C=CN=CC=1.N1C=CC=CC=1>[C:25]([O:1][C@@H:2]1[CH2:21][CH2:20][C@@:19]2([CH3:22])[C@@H:4]([CH2:5][CH2:6][C@@H:7]3[C@@H:18]2[CH2:17][CH2:16][C@@:15]2([CH3:23])[C@H:8]3[CH2:9][CH2:10][C@@H:11]2[C:12](=[O:14])[CH3:13])[CH2:3]1)(=[O:32])[C:26]1[CH:31]=[CH:30][CH:29]=[N:28][CH:27]=1

Participants

6

Conditions

Temperature
90 °C

Procedure

To 3α-hydroxy-5α-pregnan-20-one (464 mg, 318.5 g/m, 1.5 mmol) and 4-dimethylaminopyridine (DMAP, 195 mg, 122.17 g/m, 1.6 mmol) dissolved in 10 mL of dry pyridine was added nicotinoyl chloride hydrochloride (285 mg, 178.02 g/m, 1.6 mmol). The reaction mixture was heated at 90° C. for 5 hours and poured into 300 mL of ether. The organic layer was washed twice with saturated sodium bicarbonate, twice with water, dried over magnesium sulfate, and concentrated in vacuo to give the crude product. The crude material was filtered through a bed of silica gel using hexane/ethyl acetate (50:50) elution. The first two fractions gave the title compound (604 mg, 421 6/m, 1.43 mmol, 96%).

Workup

  1. washThe organic layer was washed twice with saturated sodium bicarbonate, twice with water
  2. dry with materialdried over magnesium sulfate
  3. concentrationconcentrated in vacuo
  4. customto give the crude product
  5. filtrationThe crude material was filtered through a bed of silica gel
  6. washhexane/ethyl acetate (50:50) elution

Sources & evidence

ORD record
ord-0d00213721f34e9290417906754dafe7
Source dataset
uspto-grants-1997_01
Patent number
US05591733

Linked notes

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