p-Toluenesulfonic acid → 2-[(6-bromohexyl)oxy]tetrahydro-2H-pyran

Participants

Reaction Conditions

Reaction Steps

Bromohexanol (54.67 g) is dissolved in TBME (250 mL) and dried over Na2SO4. After filtration, TsOH (0.6 mmol) is added and the solution is cooled in an ice bath. 3,4-Dihydropyran (394 mmol) is added dropwise, while maintaining the temperature around 2-3° C. After complete addition the reaction mixture is allowed to reach ambient temperature overnight. The mixture is ished with sat. NaHCO3 (2×200 mL). The aqueous layer is extracted with TBME (200 mL) and the combined organic layers are ished with brine (200 mL). After drying over Na2SO4 (containing some K2CO3), the solvent is evaporated to yield (XX) as a colourless oil (90%), which is stored at 4° C. over K2CO3 and is used without further purification.

Provenance & Evidence