Triethylamine → N2-(4-bromophenyl)-7-isopropyl-1,3-benzoxazol-2-amine

HRID 897947Notes

Reaction equation

HRID 897947 reaction equation
[NH2:1][C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([CH:8]([CH3:10])[CH3:9])[C:3]=1[OH:11].[Br:12][C:13]1[CH:18]=[CH:17][C:16]([N:19]=[C:20]=S)=[CH:15][CH:14]=1.C(N(CC)CC)C.C(OCC)(=O)C>O1CCCC1.S([O-])([O-])(=O)=O.[Cu+2]>[Br:12][C:13]1[CH:18]=[CH:17][C:16]([NH:19][C:20]2[O:11][C:3]3[C:4]([CH:8]([CH3:9])[CH3:10])=[CH:5][CH:6]=[CH:7][C:2]=3[N:1]=2)=[CH:15][CH:14]=1

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 8857Ethyl AcetateHCID 161334-Bromophenyl isothiocyanateHCID 146849822-Amino-6-isopropylphenol

Product 1

HCID 22347135N2-(4-bromophenyl)-7-isopropyl-1,3-benzoxazol-2-amineYield 91%

Reagents, catalysts & solvents 2

HCID 24462Copper SulfateCatalystHCID 8028TetrahydrofuranSolvent

Procedure

A solution of 2-amino-6-isopropylphenol (0.354 g, 2.34 mmol) and 4-bromophenylisothiocyanate (0.500 g, 2.34 mmol) in tetrahydrofuran (35 mL) was stirred at room temperature for 3 h. Anhydrous copper (II) sulfate (3.361 g, 21.06 mmol), silica gel (3.361 g), and triethylamine (0.236 g, 0.33 mL, 2.34 mmol) were added, and the mixture stirred at room temperature for 18 h. The reaction mixture was filtered through a pad of Celite and the washed with diethyl ether (3×50 mL). The filtrate was concentrated to afford a brown solid. The solid material was applied to silica gel and passed through a pad a silica gel along with ethyl acetate (3×50 mL). The filtrate was concentrated to afford N2-(4-bromophenyl)-7-isopropyl-1,3-benzoxazol-2-amine (0.702 g, 91%). RP-HPLC Rt 18.066 min, 86% purity (5% to 85% acetonitrile/0.1M aqueous ammonium acetate, buffered to pH 4.5, over 20 min at 1 mL/min; λ=254 nm; Deltapak C18, 300 Å, 5 μm, 150×3.9 mm column); m/z 333 (MH+).

Workup

  1. filtrationThe reaction mixture was filtered through a pad of Celite
  2. washthe washed with diethyl ether (3×50 mL)
  3. concentrationThe filtrate was concentrated
  4. customto afford a brown solid
  5. concentrationThe filtrate was concentrated

Sources & evidence

ORD record
ord-31a65eb9c2184af09e1d502cb1c8c288
Source dataset
uspto-grants-2005_07
Patent number
US06921763B2

Reaction notes

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