Hydrochloric Acid → HCID 19701559, compound

HRID 862078Notes

Reaction equation

HRID 862078 reaction equation
[Br:1][C:2]1[CH:3]=[CH:4][C:5]([O:21]COC)=[C:6]([CH:20]=1)[C:7]([C:9]1[C:14]([CH:15]2OCC[O:16]2)=[CH:13][CH:12]=[CH:11][N:10]=1)=[O:8].Cl.[OH-].[Na+]>C1COCC1>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([OH:21])=[C:6]([CH:20]=1)[C:7]([C:9]1[C:14]([CH:15]=[O:16])=[CH:13][CH:12]=[CH:11][N:10]=1)=[O:8]

Participants

5

Reactant 3

HCID 313Hydrochloric AcidHCID 14798Sodium HydroxideHCID 54343830HCID 54343830, compound

Product 1

HCID 19701559HCID 19701559, compoundYield 97.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

A mixture solution of 2-(5-bromo-2-methoxymethoxybenzoyl)-3-(1,3-dioxolan-2-yl)pyridine (4.27 g), hydrochloric acid (9 ml) and THF (81 ml) was stirred for 14 hours at room temperature. The reaction mixture was neutralized with an aqueous sodium hydroxide, followed by extraction with ethyl acetate. The extract solution was washed with a saturated aqueous saline solution, dried (anhydrous sodium sulfate) and concentrated. The concentrate was purified by means of a silica gel column chromatography (eluent: ethyl acetate/hexane) to give a mixture (3.22 g) of 2-(5-bromo-2-hydroxybenzoyl)-3-formylpyridine and 2-(5-bromo-2-hydroxybenzoyl)-3-(1,3-dioxolan-2-yl)pyridine (about 7:2). A mixture of the said mixture (3.22 g), ethylene glycol (560 mg), p-toluenesulfonic acid monohydrate (170 mg) and toluene (40 ml) was subjected to heating under reflux azeotropically. The reaction mixture was poured into water, which was subjected to extraction with ethyl acetate. The extract solution was washed with a saturated aqueous saline solution, dried (anhydrous sodium sulfate) and concentrated. The concentrate was purified by means of a silica gel column chromatography (eluent: ethyl acetate/hexane) to give 2-(5-bromo-2-hydroxybenzoyl)-3-(1,3-dioxolan-2-yl)pyridine (2.92 g) (Compound E-2). The physical properties and spectrum data are shown in Table 16 and Table 18.

Workup

  1. extractionfollowed by extraction with ethyl acetate
  2. washThe extract solution was washed with a saturated aqueous saline solution
  3. dry with materialdried (anhydrous sodium sulfate)
  4. concentrationconcentrated
  5. customThe concentrate was purified by means of a silica gel column chromatography (eluent: ethyl acetate/hexane)

Sources & evidence

ORD record
ord-a022a4ddbb5a469f80a574523ff3ea8b
Source dataset
uspto-grants-1998_02
Patent number
US05716971

Reaction notes

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