3,4-dihydro-2H-pyran → HCID 86661718, compound

Participants

Reaction Steps

To a solution of 2-bromo-5-hydroxybenzaldehyde (10 g, 49.75 mmol) and 3,4 dihydro-2H-pyran (4.96 mL, 54.7 mmol) in CH2Cl2 (35 mL) was added camphorsulfonic acid (230 mg, 0.99 mmol), and the mixture was stirred at room temperature for 21 h. The reaction mixture was then quenched with equal volumes of 0.2 M NaOH and EtOAc (1:1, 70 mL) before the layers were separated. The water phase was further extracted with equal volume of EtOAc before the organic layers were combined and dried over anhydrous Na2SO4 and filtered. The solvent was removed under reduced pressure. The residue was purified by silica gel column using Combiflash to give 2-bromo-5-(tetrahydro-2H-pyran-2-yloxy)benzaldehyde (2.22 g, 20%).

Provenance & Evidence