3-CHLORO-6,7-DIHYDRO[1,4]DIOXINO[2,3-C]PYRIDAZINE

3-CHLORO-6,7-DIHYDRO[1,4]DIOXINO[2,3-C]PYRIDAZINE Property

Boiling point:

351.2±42.0 °C(Predicted)

Density 

1.478±0.06 g/cm3(Predicted)

storage temp. 

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

pka

1.52±0.20(Predicted)

Appearance

White to yellow Solid

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H302Harmful if swallowed

H315Causes skin irritation

H320Causes eye irritation

H335May cause respiratory irritation

Precautionary statements

P261Avoid breathing dust/fume/gas/mist/vapours/spray.

P280Wear protective gloves/protective clothing/eye protection/face protection.

P301+P312IF SWALLOWED: call a POISON CENTER or doctor/physician IF you feel unwell.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

3-CHLORO-6,7-DIHYDRO[1,4]DIOXINO[2,3-C]PYRIDAZINE Chemical Properties,Usage,Production

Synthesis

General procedure for the synthesis of 3-chloro-6,7-dihydro[1,4]dioxohexa[2,3-c]pyridazine from the compound (CAS:17284-80-9): (c) 2-[(3,6-dichloro-4-pyridazinyl)oxy]ethanol (15.46 g; 0.0703 mol) containing the bromine derivative was dissolved in anhydrous dioxane (1.2 L). Lithium hydride (2.3 g; 0.28 mol) was added in batches and stirred under argon protection at room temperature for 1 h. The reaction was then heated to 110 °C overnight. Upon completion of the reaction, the reaction was quenched with wet dioxane and then quenched with ice water. The reaction solution was concentrated to half of the original volume, the pH was adjusted to 8 with 5 M hydrochloric acid and then evaporated to dryness. After addition of water, the residue was extracted with chloroform and the organic phase was dried over sodium sulfate and concentrated to give a white solid (12.4 g, ~77% yield, containing ~15% bromine derivative). Mass spectrometric analysis (positive ion electrospray) showed m/z 173/5 (Cl MH+) and 217/9 (Br MH+).

References

[1] Patent: US2008/221110, 2008, A1. Location in patent: Page/Page column 18
[2] Bioorganic and Medicinal Chemistry Letters, 2016, vol. 26, # 10, p. 2464 - 2469
[3] Patent: WO2008/128953, 2008, A1. Location in patent: Page/Page column 32-33
[4] Patent: WO2008/128961, 2008, A1. Location in patent: Page/Page column 54-55
[5] Patent: WO2008/128942, 2008, A1. Location in patent: Page/Page column 124