Hydrochloric Acid → Ninhydrin

HRID 50087

Reaction equation

HRID 50087 reaction equation
[NH2:1][CH2:2][CH2:3][NH:4][CH2:5][C:6]([OH:8])=[O:7].[OH-:9].[Na+].[C:11](=[O:27])([O-])[O:12][C:13]1[CH:18]=[CH:17][C:16]([N+]([O-])=O)=[CH:15][C:14]=1[C:22](C)(C)C.Cl.[O:29]1[CH2:34][CH2:33][O:32]C[CH2:30]1>O>[C:11]([NH:1][CH2:2][CH2:3][NH:4][CH2:5][C:6]([OH:8])=[O:7])([O:12][C:13]([CH3:14])([CH3:18])[CH3:30])=[O:27].[CH:16]1[CH:15]=[C:14]2[C:22]([C:33]([OH:32])([OH:7])[C:34](=[O:29])[C:13]2=[CH:18][CH:17]=1)=[O:9]

Participants

8

Reactant 5

HCID 313Hydrochloric AcidHCID 14798Sodium Hydroxide2×HCID 312751,4-Dioxane2×HCID 428913N-(2-Aminoethyl)glycineHCID 67297514t-Butyl-p-nitrophenyl carbonate

Product 2

HCID 10236NinhydrinHCID 9834393({2-[(Tert-butoxycarbonyl)amino]ethyl}amino)acetic acid

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
0 °C

Procedure

The title compound was prepared by a modification of the procedure by Heimer, et al. Int. J. Pept., 1984, 23, 203-211 N-(2-Aminoethyl)glycine (1, 3.00 g; 25.4 mmol) was dissolved in water (50 ml), dioxane (50 ml) was added, and the pH was adjusted to 11.2 with 2 N sodium hydroxide. tert-Butyl-4-nitrophenyl carbonate (7.29 g; 30.5 mmol) was dissolved in dioxane (40 ml) and added dropwise over a period of 2 h, during which time the pH was maintained at 11.2 with 2 N sodium hydroxide. The pH was adjusted periodically to 11.2 for three more hours and then the solution was left overnight. The solution was cooled to 0° C. and the pH was carefully adjusted to 3.5 with 0.5 M hydrochloric acid. The aqueous solution was washed with chloroform (3×200 ml), the pH adjusted to 9.5 with 2N sodium hydroxide and the solution was evaporated to dryness, in vacuo (14 mmHg). The residue was extracted with DMF (25+2×10 ml) and the extracts filtered to remove excess salt. This results in a solution of the title compound in about 60% yield and greater than 95% purity by tlc (system 1 and visualised with ninhydrin, Rf=0.3). The solution was used in the following preparations of Boc-aeg derivates without further purification.

Workup

  1. customThe title compound was prepared by a modification of the procedure by Heimer, et al. Int
  2. additionadded dropwise over a period of 2 h, during which time the pH
  3. washThe aqueous solution was washed with chloroform (3×200 ml)
  4. customthe solution was evaporated to dryness, in vacuo (14 mmHg)
  5. extractionThe residue was extracted with DMF (25+2×10 ml)
  6. filtrationthe extracts filtered
  7. customto remove excess salt

Sources & evidence

ORD record
ord-882cceab60494c079667750aa17885c8
Source dataset
uspto-grants-2004_03
Patent number
US06710163B1

Linked notes

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