تفاعل #938518
ord-af3009abe43d422c8481ecf383fe4cc7
معادلة التفاعل
ظروف التفاعل
المعالجة
- 1ترشيحAfter 5 hours the mixture is filtered
- 2غسيلthe celite cake is washed with methylene chloride (10×50 ml)
- 3أخرىThe solvent is removed at reduced pressure
- 4workup.ADDITIONThe residue is diluted with ether (150 ml)
- 5ترشيحfiltered
- 6أخرىthe solvent is removed at reduced pressure
- 7أخرىThe crude product (3.3 g) is chromatographed on SilicAR CC-7 (60 g)in hexane
- 8غسيلElution with 12% ethyl acetate/hexane
الإجراء التجريبي
Dry celite (30 g) and 6,6-ethylenedioxy-2-(4'-hydroxypentyl)-2-methyloxepane (3.3 g, 0.0128 mol) in methylene chloride (50 ml) are added to a pyridine-chromium trioxide solution [prepared from pyridine (12.1 g, 0.153 mol) and chromium trioxide (7.67 g, 0.0767 mol)] in distilled methylene chloride (450 ml) at 10° C. in a nitrogen atmosphere. After 5 hours 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 (150 ml), filtered and the solvent is removed at reduced pressure. The crude product (3.3 g) is chromatographed on SilicAR CC-7 (60 g)in hexane. Elution with 12% ethyl acetate/hexane gives 6,6-ethylenedioxy-2-methyl-2-(4'-oxopentyl)-oxepane as a clear colorless oil (2.1 g, 64%).