Reacción #62612

Ecuación de reacción

oxalyl chloride

4-[trimethyl[silyl]oxy]-2H-benzothiopyran

→

brown crystalline solid

Rendimiento 82.3%

4H-[1]-Benzothiopyrano[4,3-b]furan-2,3-dione

Rendimiento 82.3%

Disolventes

diethyl ether

ether

Condiciones de reacción

Tratamiento posterior

1. 1
   Otroprepared
2. 2
   Otrowas removed under reduced pressure
3. 3
   OtroThe residue was triturated with isopropyl ether/hexane

Procedimiento

To a stirred mixture of 4-[trimethyl[silyl]oxy]-2H-benzothiopyran (380.5 g, 1.609 mol), prepared according to the method of L. Hellberg et al, Tet. Letters, 3553-3554 (1974), and one liter of diethyl ether, were added 103.8 g (0.818 mol) of oxalyl chloride in a dropwise manner over a period of 50 minutes at room temperature under nitrogen. The mixture was stirred at room temperature for 17 hours after which time the ether was removed under reduced pressure. The residue was triturated with isopropyl ether/hexane to give 146.9 g (82.3%) of a brown crystalline solid, mp 156° C. (dec).

Fuente