1,3-Dibromobenzene → 4-(3-Bromophenyl)-tetrahydro-2H-pyran-4-ol
Reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([Br:8])[CH:3]=1.C([Li])CCC.CCCCCC.[O:20]1[CH:25]=[CH:24][C:23](=[O:26])[CH:22]=[CH:21]1>C1COCC1>[Br:8][C:4]1[CH:3]=[C:2]([C:23]2([OH:26])[CH2:24][CH2:25][O:20][CH2:21][CH2:22]2)[CH:7]=[CH:6][CH:5]=1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 1
Procedure
To a stirred −78° C. solution of 1,3-dibromobenzene (19.71 g, 81.05 mmol) in THF (150 mL) is added 1.6 M butyl lithium in hexane (50.66 mL, 81.05 mmol) and the reaction is stirred 10 minutes. 4H-Pyran-4-one, tetrahydro- (5.41 g, 54.04 mmol) is added dropwise and the reaction is stirred at −78° C. for 2 h. The reaction is quenched by addition of saturated aqueous ammonium chloride (25 mL) and is then diluted with minimal water and extracted with EtOAc. The organic layer is dried over Na2SO4 and the solvent is removed under reduced pressure to afford a residue that is purified by silica gel chromatography eluting with a linear gradient of 5% to 100% EtOAc in hexanes to give the title compound (11.18 g, 76%). GC-MS (m/e): (79Br/81Br) 256, 258 (M−1).
Workup
- stirringthe reaction is stirred at −78° C. for 2 h
- customThe reaction is quenched by addition of saturated aqueous ammonium chloride (25 mL)
- additionis then diluted with minimal water
- extractionextracted with EtOAc
- dry with materialThe organic layer is dried over Na2SO4
- customthe solvent is removed under reduced pressure
- customto afford a residue that
- customis purified by silica gel chromatography
- washeluting with a linear gradient of 5% to 100% EtOAc in hexanes
Sources & evidence
- ORD record
- ord-ccddfd7d55b64b2e9e7c17975147f7ed
- Source dataset
- uspto-grants-2012_10
- Patent number
- US08278441B2
Reaction notes
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