Isopropanol → Ammonia

HRID 969299Notes

Reaction equation

HRID 969299 reaction equation
Br[C:2]1[N:7]=[CH:6][C:5]([N:8]2[CH2:13][CH2:12][N:11]([C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:10][CH2:9]2)=[CH:4][CH:3]=1.[C:21]1(B(O)O)[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1.C(=O)([O-])[O-].[K+].[K+].C(O)(C)C.[OH-].[Na+]>COCCOC.O>[NH3:7].[C:21]1([C:2]2[N:7]=[CH:6][C:5]([N:8]3[CH2:13][CH2:12][N:11]([C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:10][CH2:9]3)=[CH:4][CH:3]=2)[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1

Participants

9

Reactant 5

HCID 3776IsopropanolHCID 11430Potassium CarbonateHCID 14798Sodium HydroxideHCID 66827Phenylboronic AcidHCID 11530243Tert-butyl 4-(6-bromopyridin-3-yl)piperazine-1-carboxylate

Product 2

HCID 222AmmoniaHCID 68497533HCID 68497533, compound

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 80711,2-DimethoxyethaneSolvent

Procedure

A mixture of 1-(6-bromo-3-pyridyl)-4-tert-butoxycarbonylpiperazine (1.0 g, 2.9 mmol), phenyl boronic acid (1.06 g, 8.8 mmol), aqueous potassium carbonate (4.3 ml, 8.7 mmol), water (4.3 ml), isopropanol (0.66 ml, 8.7 mmol), 1.2-dimethoxyethane (10 ml) and palladium (0) tetrakis triphenylphosphine (66 mg, 0.058 mmol) was stirred at reflux for 4 days. Aqueous sodium hydroxide (50 ml) was added and the mixture was extracted with methylene chloride (3×50 ml). Chromatography of this crude mixture on silica gel with dichloromethane, methanol and conc. ammonia (89:10:1) gave 1-(6-phenyl-3-pyridyl)-4-tert-butoxycarbonylpiperazine. The intermediate (0.80 g, 2.4 mmol), trifluoroacetic acid (1.8 ml, 23.6 mmol) and dichloromethane (10 ml) was stirred for 1.5 hour. The mixture was evaporated. Aqueous sodium hydroxide (50 ml, 1 M) was was added and the mixture was extracted with diethyl ether (3×50 ml). The corresponding salt was obtained by addition of a diethyl ether and methanol mixture (9:1) saturated with fumaric acid. Mp 203-204° C.

Workup

  1. temperatureat reflux for 4 days
  2. extractionthe mixture was extracted with methylene chloride (3×50 ml)

Sources & evidence

ORD record
ord-1eab60a2b3a043339db73feedb0d7df0
Source dataset
uspto-grants-2007_12
Patent number
US07307087B2

Reaction notes

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