3-bromo-6-methylpyridazine Chemical Properties

Boiling point:

285.0±20.0 °C(Predicted)

Density 

1.596±0.06 g/cm3(Predicted)

storage temp. 

under inert gas (nitrogen or Argon) at 2-8°C

solubility 

DMSO (Slightly), Methanol (Slightly)

pka

1.26±0.10(Predicted)

form 

Solid

color 

Dark Brown

InChI

InChI=1S/C5H5BrN2/c1-4-2-3-5(6)8-7-4/h2-3H,1H3

InChIKey

RACIHBXDZONTQJ-UHFFFAOYSA-N

SMILES

C1(Br)=NN=C(C)C=C1

Safety Information

HS Code 

2933998090

3-bromo-6-methylpyridazine Usage And Synthesis

Uses

3-Bromo-6-methylpyridazine is used as a reagent in the synthesis of piperazinyl quinolines as chemosensitizers to increase fluconazole susceptibility of Candida albicans. 3-Bromo-6-methylpyridazine is also used in the preparation of cyclohexyl fluoropyrimidinyl benzamides as CNS penetrable P2X7 receptor antagonists.

Synthesis

6-Methyl-3(2H)-pyridazinone (18 g, 163.44 mmol) was mixed with phosphorus tribromide oxide (93.8 g, 327.6 mmol) and the reaction was stirred at 70 °C overnight. Upon completion of the reaction, the reaction mixture was cooled to 40 °C and quenched by slowly pouring it into ice water. Subsequently, the reaction mixture was neutralized with saturated sodium bicarbonate solution (20 mL) and extracted with dichloromethane (100 mL x 3). The organic phases were combined, dried with anhydrous sodium sulfate, filtered and concentrated under reduced pressure to afford the target product 3-bromo-6-methylpyridazine (8 g, 31% yield). The product was detected by LCMS (ESI), m/z: 173 [M + 1]+. 1H NMR (chloroform-d, Bruker Avance 400MHz) data were as follows: δ 7.86-7.88 (d, 1H, J = 8Hz), 7.52-7.54 (d, 1H, J = 8Hz), 2.55 (s, 3H).

References

[1] Patent: EP3333157, 2018, A1. Location in patent: Paragraph 0136; 0137
[2] Patent: WO2010/36998, 2010, A2. Location in patent: Page/Page column 184