4-Toluenesulfonyl chloride → Tert-butoxycarbonyl-4-(4-toluenesulfonyloxyethyl)-2,2-dimethyloxazolidine

HRID 993479Notes

Reaction equation

HRID 993479 reaction equation
[C:1]1([CH3:11])[CH:6]=[CH:5][C:4]([S:7](Cl)(=[O:9])=[O:8])=[CH:3][CH:2]=1.[C:12]([O:16][C:17]([N:19]1[C@@H:23]([CH2:24][CH2:25][OH:26])[CH2:22][O:21][C:20]1([CH3:28])[CH3:27])=[O:18])([CH3:15])([CH3:14])[CH3:13].C(N(CC)CC)C>CN(C)C1C=CN=CC=1.ClCCl>[C:12]([O:16][C:17]([N:19]1[CH:23]([CH2:24][CH2:25][O:26][S:7]([C:4]2[CH:5]=[CH:6][C:1]([CH3:11])=[CH:2][CH:3]=2)(=[O:9])=[O:8])[CH2:22][O:21][C:20]1([CH3:28])[CH3:27])=[O:18])([CH3:15])([CH3:14])[CH3:13]

Participants

6

Reactant 3

HCID 73974-Toluenesulfonyl chlorideHCID 8471TriethylamineHCID 10847957tert-butyl (4S)-4-(2-hydroxyethyl)-2,2-dimethyl-1,3-oxazolidine-3-carboxylate2×

Product 1

HCID 86758585Tert-butoxycarbonyl-4-(4-toluenesulfonyloxyethyl)-2,2-dimethyloxazolidineYield 90.6%

Reagents, catalysts & solvents 2

HCID 142844-(Dimethylamino)pyridineCatalystHCID 6344DichloromethaneSolvent

Procedure

Dry, freshly crystallised p-toluenesulphonyl chloride (1.86 g, 9.8 mmol) and 4-dimethylaminopyridine (10 mg, 0.082 mmol) were added to a solution of alcohol 5 (2.00 g, 8.15 mmol) and triethylamine (2.6 ml, 18.75 mmol) in dichloromethane (20 ml) at 5° C. with stirring. The resulting solution was protected from moisture and kept at 5° C. until all the starting material 5 had reacted (33 h, TLC). A colourless solid, presumably triethylamine hydrochloride, crystallised out of the reaction, and was filtered away. The filtrate was diluted with dichloromethane to a volume of 90 ml, and washed with water (2×20 ml), brine (20 ml), dried over Na2SO4, and concentrated to give the crude tosylate 7 as white solid. This material was purified by dissolving in ether (ca. 330 ml), filtering through celite 545 on a wad of cotton wool to give 2.95 g (90%) of 7. 1H NMR (200 MHz, CDCl3) 7.78 (m, 2H), 7.35 (d, 2H), 4.09 (m, 2H), 4.09 (m, 2H), 3.90 (m, 2H), 3.73 (m, 1H), 2.95 (m, 2H), 1.51 (s, 6H), 1.44 (s, 9H).

Workup

  1. customDry
  2. customkept at 5° C. until all
  3. customhad reacted (33 h, TLC)
  4. customA colourless solid, presumably triethylamine hydrochloride, crystallised out of the reaction
  5. filtrationwas filtered away
  6. additionThe filtrate was diluted with dichloromethane to a volume of 90 ml
  7. washwashed with water (2×20 ml), brine (20 ml)
  8. dry with materialdried over Na2SO4
  9. concentrationconcentrated
  10. customto give the crude tosylate 7 as white solid
  11. customThis material was purified
  12. dissolutionby dissolving in ether (ca. 330 ml)
  13. filtrationfiltering through celite 545 on a wad of cotton wool

Sources & evidence

ORD record
ord-402934a1f91b48b6a2cf069ff98bc675
Source dataset
uspto-grants-2002_10
Patent number
US06472533B1

Reaction notes

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