2,2-Dimethoxypropane → 143364-85-6

HRID 1424212Notes

Reaction equation

HRID 1424212 reaction equation
[C:1]([NH:8][C@H:9]([C:13]([OH:15])=[O:14])[C@@H:10]([CH3:12])[OH:11])([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].CO[C:18](C)([CH3:20])[CH3:19].COC(OC)(C)C.C1(C)C=CC(S([O-])(=O)=O)=CC=1.[NH+]1C=CC=CC=1>O.C1COCC1>[C:4]([O:3][C:1]([N:8]1[C@H:9]([C:13]([OH:15])=[O:14])[C@@H:10]([CH3:12])[O:11][C:18]1([CH3:20])[CH3:19])=[O:2])([CH3:6])([CH3:5])[CH3:7]

Participants

7

Reactant 4

HCID 64952,2-DimethoxypropaneHCID 15413tert-Butyl methyl etherHCID 466102Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1)HCID 2724766N-tert-Butoxycarbonyl-L-threonine

Product 1

HCID 10956272143364-85-6

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8028TetrahydrofuranSolvent

Procedure

Boc-L-threonine (600 g, 2.74 mol) was added to methyl-tert-butyl ether (3.6 L) and THF (1.2 L) followed by 2,2-dimethoxypropane (1710 g, 16.42 mol) and pyridinium p-toluenesulfonate (171.9 g, 684 mmol) and the suspension heated to reflux for 20 hours. The reaction was cooled and diluted with water (3 L) and stirred to achieve a solution. The organic layer was collected, washed with water (1.8 L), and diluted with methyl-tert-butyl ether (4.2 L). A solution of NaOH in water (109 g in 120 mL) was added and the mixture stirred for 20 minutes. The mixture was concentrated to low volume to effect precipitation. The resulting solid was filtered and collected as the sodium salt of the title compound.

Workup

  1. temperaturethe suspension heated
  2. temperatureto reflux for 20 hours
  3. temperatureThe reaction was cooled
  4. customThe organic layer was collected
  5. washwashed with water (1.8 L)
  6. additiondiluted with methyl-tert-butyl ether (4.2 L)
  7. additionA solution of NaOH in water (109 g in 120 mL) was added
  8. stirringthe mixture stirred for 20 minutes
  9. concentrationThe mixture was concentrated to low volume to effect precipitation
  10. filtrationThe resulting solid was filtered
  11. customcollected as the sodium salt of the title compound

Sources & evidence

ORD record
ord-8b08b2abde614085b69005c1d8db34eb
Source dataset
uspto-grants-2015_01
Patent number
US08927587B2

Reaction notes

Loading…