Ethylene Glycol → 2-Bromo-5-(1,3-dioxolan-2-YL)pyridine

HRID 78254Notes

Reaction equation

HRID 78254 reaction equation
[Br:1][C:2]1[N:7]=[CH:6][C:5]([CH:8]=[O:9])=[CH:4][CH:3]=1.[CH2:10](O)[CH2:11][OH:12].C1(C)C=CC(S(O)(=O)=O)=CC=1.C1(C)C=CC=CC=1>O>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH:8]2[O:12][CH2:11][CH2:10][O:9]2)=[CH:6][N:7]=1

Participants

6

Reactant 4

HCID 174Ethylene GlycolHCID 1140TolueneHCID 6101p-Toluenesulfonic acidHCID 117692346-Bromo-3-pyridinecarboxaldehyde

Product 1

HCID 184696682-Bromo-5-(1,3-dioxolan-2-YL)pyridineYield 59%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A mixture of 6-bromo-pyridine-3-carbaldehyde (8.0 g, 43 mmol) described in Manufacturing Example 210-1-1, ethylene glycol (5.3 g, 86 mmol), p-toluenesulfonic acid (820 mg, 4.3 mmol), and toluene (110 mL) was stirred for 40 minutes under reflux. (The water produced in this reaction was removed with a Dean-Stark trap.) The reaction solution was concentrated under a reduced pressure, and the residue was partitioned into ethyl acetate and water. The organic layer was separated and passed through a glass filter provided with NH silica gel (eluted with ethyl acetate). The eluate was concentrated under a reduced pressure, and the residue was purified by silica gel column chromatography (heptane:ethyl acetate=8:1) to obtain the title compound (5.8 g, 59%).

Workup

  1. temperatureunder reflux
  2. customwas removed with a Dean-Stark trap
  3. concentration) The reaction solution was concentrated under a reduced pressure
  4. customthe residue was partitioned into ethyl acetate and water
  5. customThe organic layer was separated
  6. filtrationfilter
  7. customprovided with NH silica gel (eluted with ethyl acetate)
  8. concentrationThe eluate was concentrated under a reduced pressure
  9. customthe residue was purified by silica gel column chromatography (heptane:ethyl acetate=8:1)

Sources & evidence

ORD record
ord-314f39c214ff47c98534777d7d8c92cf
Source dataset
uspto-grants-2014_09
Patent number
US08841327B2

Reaction notes

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