2,4-Dichloro-6,7-dimethoxyquinazoline

2,4-Dichloro-6,7-dimethoxyquinazoline Property

Melting point:

175-178 °C (lit.)

Boiling point:

340.5±42.0 °C(Predicted)

Density 

1.5369 (rough estimate)

refractive index 

1.6100 (estimate)

storage temp. 

2-8°C

solubility 

Chloroform (Slightly), DMSO (Slightly), Methanol (Slightly)

pka

-0.49±0.30(Predicted)

form 

Crystalline Powder

color 

Pale yellow to beige

Water Solubility 

Insoluble in water.

Sensitive 

Moisture Sensitive

BRN 

190331

CAS DataBase Reference

27631-29-4(CAS DataBase Reference)

Safety

Hazard Codes 

Xi

Risk Statements 

36/37/38

Safety Statements 

37/39-26-36

WGK Germany 

3

HS Code 

29334900

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H315Causes skin irritation

H319Causes serious eye irritation

H335May cause respiratory irritation

Precautionary statements

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

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P271Use only outdoors or in a well-ventilated area.

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

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.

2,4-Dichloro-6,7-dimethoxyquinazoline Chemical Properties,Usage,Production

Chemical Properties

pale yellow to beige crystalline powder

Uses

An intermediate in the preparation of potential inhibitors of epidermal growth factor receptor kinases. An intermediate in the preparation of Terazosin (T105000).

Uses

2,4-Dichloro-6,7-dimethoxyquinazoline is used as an intermediate in the preparation of potential inhibitors of epidermal growth factor receptor kinases. It is also used as an intermediate in the preparation of terazosin.

Synthesis

The general procedure for the synthesis of 2,4-dichloro-6,7-dimethoxyquinazoline from 6,7-dimethoxy-2,4-quinazolinedione was as follows: in a 100 mL three-necked flask equipped with a reflux condenser, 6,7-dimethoxy-2,4-quinazolinedione (1.00 g) and phosphorus triclosan (15 mL; 24.77 g; 161.53 mmol) were added, the reaction mixture was refluxed at 100 °C in an oil bath with stirring for 24 hours. Upon completion of the reaction, the reaction solution was cooled to room temperature and the reaction was quenched by slowly pouring it into an ice-water mixture under vigorous stirring. The precipitated solid was collected by vacuum filtration and the crude product was purified by silica gel column chromatography using dichloromethane as eluent.

References

[1] Journal of Medicinal Chemistry, 1986, vol. 29, # 5, p. 627 - 629
[2] European Journal of Medicinal Chemistry, 2014, vol. 71, p. 1 - 14
[3] Patent: WO2004/13091, 2004, A2. Location in patent: Page 34-35
[4] The Journal of organic chemistry, 2002, vol. 67, # 23, p. 8284 - 8286
[5] Journal of the Chemical Society, 1948, p. 1759,1765