[Br:1][C:2]1[CH:7]=[CH:6][C:5]([OH:8])=[CH:4][CH:3]=1.CC(C)([O-])C.[K+].Br[CH2:16][CH2:17][O:18][CH:19]1[CH:24]=[CH:23][CH:22]=[CH:21][O:20]1>CS(C)=O.[Cl-].[Na+].O>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([O:8][CH2:16][CH2:17][O:18][CH:19]2[CH2:24][CH2:23][CH2:22][CH2:21][O:20]2)=[CH:4][CH:3]=1To a solution of 4-bromophenol (1.71 g, 9.91 mmol) in DMSO (40 mL) was added potassium t-butoxide (1.17 g, 10.4 mmol) and the mixture was stirred for 20 mins. Tetrahydro-2-(2-bromoethoxy-2H-pyran (2.18 g, 10.4 mmol) in DMSO (10 mL) was added dropwise and the reaction was stirred for 1 hr. It was then diluted with brine (100 mL) and extracted with ethylacetate (3×100 mL). The organics were combined, dried with MgSO4 and concentrated. The resulting residue was chromatographed (silica gel, hexanes:ether, 85:15) to afford tetrahydro-2-(2-(4-bromophenoxy)ethoxy)-2H-pyran (2.52 g, 85%) as a colorless oil.
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