Dibromomethane → 6-bromo-2H-[1,3]dioxolo[4,5-b]pyridine

HRID 2170036Notes

Reaction equation

HRID 2170036 reaction equation
[Br:1][C:2]1[CH:3]=[C:4]([OH:9])[C:5]([OH:8])=[N:6][CH:7]=1.[C:10]([O-])([O-])=O.[K+].[K+].BrCBr.CCOC(C)=O>CN1C(=O)CCC1>[Br:1][C:2]1[CH:3]=[C:4]2[O:9][CH2:10][O:8][C:5]2=[N:6][CH:7]=1

Participants

6

Reactant 4

HCID 3024DibromomethaneHCID 8857Ethyl AcetateHCID 11430Potassium CarbonateHCID 178515448HCID 178515448, compound

Product 1

HCID 125630906-bromo-2H-[1,3]dioxolo[4,5-b]pyridine

Reagents, catalysts & solvents 1

HCID 13387N-methyl-2-pyrrolidoneSolvent

Conditions

Temperature
90 °C

Procedure

To a suspension of 5-Bromo-pyridine-2,3-diol (10.0 g, 52.63 mmol, commercially available, CAS 34206-49-0) in NMP (100 mL) was added K2CO3 (21.97 g, 158 mmol) and dibromo methane (10.97 g, 63.16 mmol). The reaction mixture was heated to 90° C. for 16 h. EtOAc was added and the salts were filtered off. Water was added, the phases were separated and the aq layer was extracted with more ethyl acetate. The combined organic layers was dried over anhydrous Na2SO4 and concentrated under vacuo to get the crude compound. The crude compound was purified by silica gel chromatography (eluent 5% ethyl acetate in petrol ether). Yield of 6-Bromo-[1,3]dioxolo[4,5-b]pyridine 2.2 g (21%) pure by 1H NMR (400 MHz, DMSO) δ 7.71 (d, 1H, J=2 Hz), 7.55 (d, 1H, J=2 Hz), 6.20 (s, 2H). Mp 69-71 C.

Workup

  1. filtrationthe salts were filtered off
  2. additionWater was added
  3. customthe phases were separated
  4. extractionthe aq layer was extracted with more ethyl acetate
  5. dry with materialThe combined organic layers was dried over anhydrous Na2SO4
  6. concentrationconcentrated under vacuo

Sources & evidence

ORD record
ord-3376832106884685b79edc450f2bd8e8
Source dataset
uspto-grants-2015_06
Patent number
US09050327B2

Reaction notes

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