Urea → HCID 178422339, compound

Temperature

180 °C

A mixture of methyl 3-amino-5-methylthiophene-2-carboxylic acid (1.2 g) and urea (2.2 g) was stirred at 180° C. for 2.5 h. The mixture was left stand for cooling to room temperature, followed by 1 M aqueous sodium hydroxide (20 mL), the solids were dissolved, and the mixture was neutralized with acetic acid. The precipitated crystals were collected by filtration to obtain 6-methylthieno[3,2-d]pyrimidine-2,4-diol (0.77 g). (2) To a mixture of 6-methylthieno[3,2-d]pyrimidine-2,4-diol (0.77 g) and phosphorus oxychloride (8 mL) was added N,N-dimethylaniline (1.6 mL) at room temperature, and the mixture was stirred at 100° C. for 2 h. The reaction solution was added dropwise to water with ice cooling, and the aqueous layer was extracted with chloroform. The organic layer was concentrated under reduced pressure, and the residue was purified by silica gel column chromatography (silica gel, chloroform) to obtain 2,4-dichloro-6-methylthieno[3,2-d]pyrimidine (0.50 g).

1. waitThe mixture was left stand
2. temperaturefor cooling to room temperature
3. dissolutionthe solids were dissolved
4. filtrationThe precipitated crystals were collected by filtration

ORD record

ord-cee1d39e77db430180fd0260c7e0cc57

Source dataset

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08044068B2