Reacción #95307

Ecuación de reacción

4-hydroxy-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one

sodium bicarbonate

p-toluenesulfonic acid monohydrate

sodium chloride

dihydropyran

→

4-tetrahydropyranyloxy-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one

Disolventes

ether

MeOH

methylene chloride

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe organic phase is separated
2. 2
   Lavadowashed with saturated sodium chloride solution
3. 3
   SecadoThe extract is dried over magnesium sulfate, and volatile matter
4. 4
   Otrois evaporated at reduced pressure
5. 5
   Otroto give an oil, λmax

Procedimiento

To a stirred solution of 674 mg. (2.64 mmoles) of 4-hydroxy-2-(6-carbethoxyhexyl)cyclopent-2-en-1-one (Example 1302) and 2.22 g. (26.4 mmoles) of dihydropyran in 2.6 ml. of methylene chloride is added 5.0 mg. (0.026 moles) of p-toluenesulfonic acid monohydrate. After stirring for 20 minutes at room temperature the solution is diluted with ether and poured into saturated sodium chloride solution containing a little sodium bicarbonate. The organic phase is separated and washed with saturated sodium chloride solution. The extract is dried over magnesium sulfate, and volatile matter is evaporated at reduced pressure to give an oil, λmax.MeOH =224 mμ (7950); max.=1735 (ester carbonyl group), 1710 (ketone carbonyl group), and 1030 cm-1 (tetrahydropyranyloxy group).

Fuente