Reaction #1470433

ord-486243e2fe984587b3502ab7b6c7581c

Reaction equation

CC1(C)CC(O)CC(C)(C)N1O
1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine
O=C(O)CC(O)(CC(=O)O)C(=O)O
citric acid
→
CC1(C)CC(O)CC(C)(C)[NH+]1O.CC1(C)CC(O)CC(C)(C)[NH+]1O.CC1(C)CC(O)CC(C)(C)[NH+]1O.O=C([O-])CC(O)(CC(=O)[O-])C(=O)[O-]
product
CC1(C)CC(O)CC(C)(C)[NH+]1O.CC1(C)CC(O)CC(C)(C)[NH+]1O.CC1(C)CC(O)CC(C)(C)[NH+]1O.O=C([O-])CC(O)(CC(=O)[O-])C(=O)[O-]
1-Hydroxy-2,2,6,6-tetramethyl-4-hydroxypiperidinium Citrate

Reactants

—
Pt
CC1(C)CC(O)CC(C)(C)N1O
1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine
O=C(O)CC(O)(CC(=O)O)C(=O)O
citric acid
—
glass

Reagents

None

Solvents

O
water

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    OtherCatalyst is removed by filtration through a pad of Celite
  2. 2
    OtherRemoval of water

Procedure

To a glass 0.5 L reaction bottle are added 20.0 g (116 mmol) of 1-oxyl-2,2,6,6-tetramethyl-4-hydroxypiperidine, 22.2 g (116 mmol) citric acid, 200 mg 5% Pt on C and 100 mL water. Catalytic hydrogenation is carried out at 50 psi for 30 minutes at room temperature. Catalyst is removed by filtration through a pad of Celite. The aqueous salt solution has a pH of 3.30. Removal of water yields the product as a hygroscopic glassy solid.

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US06254724B1uspto-grants-2001_07