Benzoyl chloride → (20S)-21-hydroxy-20-methylpregn-4-en-3-one benzoate

HRID 2082413Notes

Reaction equation

HRID 2082413 reaction equation
[OH:1][CH2:2][C@@H:3]([CH3:24])[C@@H:4]1[C@:21]2([CH3:22])[C@H:7]([C@H:8]3[C@H:18]([CH2:19][CH2:20]2)[C@:16]2([CH3:17])[C:11](=[CH:12][C:13](=[O:23])[CH2:14][CH2:15]2)[CH2:10][CH2:9]3)[CH2:6][CH2:5]1.C(N(CC)CC)C.[C:32](Cl)(=[O:39])[C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1>ClCCl>[C:32]([OH:39])(=[O:1])[C:33]1[CH:38]=[CH:37][CH:36]=[CH:35][CH:34]=1.[OH:1][CH2:2][C@@H:3]([CH3:24])[C@@H:4]1[C@:21]2([CH3:22])[C@H:7]([C@H:8]3[C@H:18]([CH2:19][CH2:20]2)[C@:16]2([CH3:17])[C:11](=[CH:12][C:13](=[O:23])[CH2:14][CH2:15]2)[CH2:10][CH2:9]3)[CH2:6][CH2:5]1

Participants

5

Procedure

A solution of (20S)-21-hydroxy-20-methylpregn-4-en-3-one (8.0 g, 24.2 mmole) in dichloromethane (200 mL) was cooled in an ice-water bath and treated sequentially with triethylamine (3.69 mL, 26.6 mmole) and benzoyl chloride (3.09 mL, 26.6 mmole) and stirred for 16 hours at room temperature. After the reaction mixture was diluted with dichloromethane (200 mL), it was extracted with ether, dried over magnesium sulfate and filtered and the filtrate was concentrated to a solid which was purified by flash chromatography to give (20S)-21-hydroxy-20-methylpregn-4-en-3-one benzoate (9.4 g, 89.5%) melting at 193°-195° C. after recrystallization from acetone. IR 1716, 1676, 1614 (m), 1284 cm-1 ; MS (CI) 435 (100%, M+1), 313 (70%, M+1 - PhCOOH); 1H NMR (CDCl3) δ0.77 (3H, S, C18 -Me), 1.04 (d, C22 -Me), 1.19 (s, C19 -Me), 4.05 (1H, dd, 1/2C21 -CH2), 4.34 (1H, dd, 1/2C21 -CH2), 5.72 (1H, s, C4 -H), 7.45 (2H, t), 7.56 (1H, t), 8.04 (2H, dd).

Workup

  1. extractionwas extracted with ether
  2. dry with materialdried over magnesium sulfate
  3. filtrationfiltered
  4. concentrationthe filtrate was concentrated to a solid which
  5. customwas purified by flash chromatography

Sources & evidence

ORD record
ord-b287eb900ecd494f9407166db7215da2
Source dataset
uspto-grants-1993_02
Patent number
US05189032

Reaction notes

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