Pyridine → HCID 53999410, compound

Participants

Reaction Steps

A solution of p-toluenesulphonic acid (20 mg) in dry dichloromethane (5 ml) was added, dropwise, to a stirred mixture of methyl (±)-7-[4-hydroxy-5-oxocyclopent-1-enyl]-hepatanoate (1.2 g; prepared as described in Example 3) and 2,3-dihydropyran in dry dichloromethane (20 ml), with cooling to maintain the temperature below 30° C. After one hour, a further quantity of 2,3-dihydropyran (0.3 g) was added dropwise, and the mixture was stirred for one hour further. Pyridine (100 mg) was added, and the mixture was washed with saturated aqueous sodium chloride solution, dried over magnesium sulphate, and evaporated in vacuo, finally at 0.1 mm Hg and 50° C. for 4 hours, to give methyl (±)-7-[4-(2-tetrahydropyranyloxy)-5-oxocyclopent-1-enyl]heptanoate (1.9 g), in the form of a brown oil, pure enough for use in the next stage without further purification.

Provenance & Evidence