Hydrochloric Acid → p-Toluenesulfonic acid

HRID 39395Notes

Reaction equation

HRID 39395 reaction equation
Cl.O.[C:3]1([CH3:13])[CH:8]=[CH:7][C:6]([S:9]([OH:12])(=[O:11])=[O:10])=[CH:5][CH:4]=1>CO>[C:3]1([CH3:13])[CH:4]=[CH:5][C:6]([S:9]([OH:12])(=[O:10])=[O:11])=[CH:7][CH:8]=1

Participants

4

Reactant 2

HCID 313Hydrochloric AcidHCID 521998p-Toluenesulfonic acid monohydrate

Product 1

HCID 6101p-Toluenesulfonic acidYield 78%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent2×

Procedure

To 15 mL of methanol, 1.30 g (prepared to be 6.87 mmol) of the hydrochloric acid salt and 1.36 g (7.15 mmol, 1.04 eq) of p-toluenesulfonic acid monohydrate were added, and dissolving under heating was made at 40 to 50° C., followed by making concentration of almost whole methanol (about 13 mL) under reduced. The precipitated crystal was filtered, and washed with a small amount of n-heptane, followed by being subjected to drying under vacuum, thereby obtaining 960 mg of p-toluenesulfonic acid salt (refined product) of α-trifluoromethyl-β-substituted-β-amino acids represented by the above-mentioned formula. The total yield from α-trifluoromethyl-β-substituted-α,β-unsaturated esters was 41%. The diastereomer ratio was syn-body:anti-body=>98:2 according to 1H- and 19F-NMR analyses.

Workup

  1. dissolutiondissolving
  2. temperatureunder heating
  3. customwas made at 40 to 50° C.
  4. filtrationThe precipitated crystal was filtered
  5. washwashed with a small amount of n-heptane
  6. customto drying under vacuum

Sources & evidence

ORD record
ord-c838757fe67d4e1ebbd68daa9b763cb7
Source dataset
uspto-grants-2013_09
Patent number
US08524913B2

Reaction notes

Loading…