2-(4'-Benzyloxybutyl)-2-methyloxepane-6-ol → 2-(4'-Benzyloxybutyl)-2-methyl-oxepan-6-one
Reaction equation
[CH2:1]([O:8][CH2:9][CH2:10][CH2:11][CH2:12][C:13]1([CH3:21])[CH2:19][CH2:18][CH2:17][CH:16]([OH:20])[CH2:15][O:14]1)[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1>C(Cl)Cl.N1C=CC=CC=1.[O-2].[O-2].[O-2].[Cr+6]>[CH2:1]([O:8][CH2:9][CH2:10][CH2:11][CH2:12][C:13]1([CH3:21])[CH2:19][CH2:18][CH2:17][C:16](=[O:20])[CH2:15][O:14]1)[C:2]1[CH:3]=[CH:4][CH:5]=[CH:6][CH:7]=1Participants
4
Reactant 1
Product 1
Reagents, catalysts & solvents 2
Procedure
Dry celite (50 g) and 2-(4'-benzyloxybutyl)-2-methyloxepane-6-ol (6.9 g, 0.02 mol) in methylene chloride are added to a pyridine-chromium trioxide solution [prepared from pyridine (22.4 g, 0.284 mol) and chouromium trioxide (14.2 g, 0.142 mol)] in dry methylene chloride (800 ml) at 10° C. in a nitrogen atmosphere. After 2 hours of stirring the mixture is filtered and the celite cake is washed with methylene chloride (10×50 ml). The solvent is removed at reduced pressure. The residue is diluted with ether (200 ml), filtered and the solvent is removed at reduced pressure. The crude product is chromatographed on SilicAR CC-7 (150 g) in hexane. Elution with 10% ethyl acetate/hexane gives 2-(4'-benzyloxybutyl)-2-methyl-oxepan-6-one (11) as a clear colorless oil (5.9 g, 86%).