Triethylamine → methanesulfonic acid 5-benzyloxy-4-oxo-4H-pyran-2-ylmethyl ester

HRID 912999Notes

Reaction equation

HRID 912999 reaction equation
[CH2:1]([O:8][C:9]1[C:10](=[O:17])[CH:11]=[C:12]([CH2:15][OH:16])[O:13][CH:14]=1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C(N(CC)CC)C.[CH3:25][S:26](Cl)(=[O:28])=[O:27].C(Cl)Cl.CO>ClCCl.CS(Cl)(=O)=O>[CH2:1]([O:8][C:9]1[C:10](=[O:17])[CH:11]=[C:12]([CH2:15][O:16][S:26]([CH3:25])(=[O:28])=[O:27])[O:13][CH:14]=1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1

Participants

7

Reactant 4

HCID 8471Triethylamine3×HCID 31297Methanesulfonyl chloride2×HCID 9015985-(benzyloxy)-2-(hydroxymethyl)-4H-pyran-4-oneHCID 21226129Dichloromethane methanol

Product 1

HCID 84562570methanesulfonic acid 5-benzyloxy-4-oxo-4H-pyran-2-ylmethyl esterYield 97.4%

Reagents, catalysts & solvents 2

HCID 31297Methanesulfonyl chlorideCatalystHCID 6344DichloromethaneSolvent2×

Procedure

To an ice/salt cooled suspension of 5-benzyloxy-2-hydroxymethyl-pyran-4-one (30.0 g, 0.129 mol) in dichloromethane (500 mL) were added, successively, triethylamine (21.0 mL, 0.151 mol) and a solution of methanesulfonyl chloride (8.3 mL, 0.129 mol) in 10 mL of dichloromethane. The progress of the reaction was monitored by TLC (CH2Cl2/MeOH, 10/1, v/v), and by HPLC Method 1 as described above. An additional methanesulfonyl chloride (0.5 mL, 7.70 mmol) and triethylamine (2.0 mL, 14.2 mmol) were added to the solution after 50 min. Again, an additional methanesulfonyl chloride (1.0 mL, 15.4 mmol) and triethylamine (2 mL, 14.2 mmol) were added an hour later. The reaction was quenched with 150 mL of brine. The organic phase was separated and collected, dried over sodium sulfate and concentrated in vacuo to give an oil. The oil was diluted with 200 mL of hexanes and a precipitate was formed. The solid was collected by suction filtration, and dried in a vacuum oven to give methanesulfonic acid 5-benzyloxy-4-oxo-4H-pyran-2-ylmethyl ester (39 g, 85% yield). HPLC purity (peak area percent) is 82.1% at λ=280 nm using HPLC Method 1 as described above. 1H NMR (400 MHz, DMSO-D6) δ (ppm): 8.32 (m, 1H), 7.43-7.37 (m, 5H), 6.62 (m, 1H), 5.18 (m, 2H, OCH2), 4.98 (m, 2H, OCH2), 3.36 (m, 3H, SCH3).

Workup

  1. additionwere added
  2. customThe reaction was quenched with 150 mL of brine
  3. customThe organic phase was separated
  4. customcollected
  5. dry with materialdried over sodium sulfate
  6. concentrationconcentrated in vacuo
  7. customto give an oil
  8. customa precipitate was formed
  9. filtrationThe solid was collected by suction filtration
  10. customdried in a vacuum oven

Sources & evidence

ORD record
ord-4c52c99f4c0c4035883d436e05ad7a75
Source dataset
uspto-grants-2011_09
Patent number
US08026261B2

Reaction notes

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