p-Toluenesulfonic acid monohydrate → t-Butyl 4-amino-3-methylphenoxyacetate, p-toluenesulphonate salt

HRID 1900893Notes

Reaction equation

HRID 1900893 reaction equation
[CH3:1][C:2]1[CH:3]=[C:4]([CH:14]=[CH:15][C:16]=1[N+:17]([O-])=O)[O:5][CH2:6][C:7]([O:9][C:10]([CH3:13])([CH3:12])[CH3:11])=[O:8].O.[C:21]1([CH3:31])[CH:26]=[CH:25][C:24]([S:27]([OH:30])(=[O:29])=[O:28])=[CH:23][CH:22]=1.[H][H]>CO.[Pd]>[C:21]1([CH3:31])[CH:22]=[CH:23][C:24]([S:27]([OH:30])(=[O:28])=[O:29])=[CH:25][CH:26]=1.[NH2:17][C:16]1[CH:15]=[CH:14][C:4]([O:5][CH2:6][C:7]([O:9][C:10]([CH3:12])([CH3:13])[CH3:11])=[O:8])=[CH:3][C:2]=1[CH3:1]

Participants

6

Reactant 3

HCID 521998p-Toluenesulfonic acid monohydrateHCID 23370041t-Butyl 3-methyl-4-nitrophenoxyacetateHCID 178418361HCID 178418361, compound2×

Product 1

HCID 131719653t-Butyl 4-amino-3-methylphenoxyacetate, p-toluenesulphonate saltYield 45.8%

Reagents, catalysts & solvents 2

HCID 23938PalladiumCatalystHCID 887MethanolSolvent

Procedure

To a solution of the product from step (a) (4.18 g) in methanol (250 ml) under argon was added p-toluenesulphonic acid monohydrate (2.99 g) followed by 10% Pd on C (1.8 g). The argon was replaced by hydrogen and the reaction mixture was stirred under a blanket of hydrogen for 6 hours. The catalyst was filtered off through a pad of diatomaceous earth and washed with methanol. The blue-coloured filtrate and washings were evaporated to near dryness and excess ether was added. On storage overnight at -10° C. a solid crystallised which was collected, washed with ether and dried to give t-butyl 4-amino-3-methylphenoxyacetate, p-toluenesulphonate salt (2.93 g) as an off-white solid: NMR Spectrum (DMSO-d6) 1.42 (9H, s), 2.28 (3H, s), 2.30 (3H, s), 4.63 (2H, s), 6.82 (1H, dd), 6.88 (1H, d), 7.12 (2H, d), 7.24 (1H, d), 7.48 (2H, d), 9.50 (3H, br s); Mass Spectrum m/Z 260 (M+Na)+.

Workup

  1. filtrationThe catalyst was filtered off through a pad of diatomaceous earth
  2. washwashed with methanol
  3. customThe blue-coloured filtrate and washings were evaporated
  4. additionwas added
  5. customOn storage overnight at -10° C. a solid crystallised which
  6. customwas collected
  7. washwashed with ether
  8. customdried

Sources & evidence

ORD record
ord-fdc5e40721254c6d9f5938127405ed0b
Source dataset
uspto-grants-1996_11
Patent number
US05576334

Reaction notes

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