تفاعل #938516

معادلة التفاعل

6,6-ethylenedioxy-2-(4'-hydroxybutyl)-2-methyloxepane

pyridine

→

6,6-ethylenedioxy-2-methyl-2-(4'-oxobutyl)-oxepane

المردود 70.0%

6,6-Ethylenedioxy-2-methyl-2-(4'-oxobutyl)-oxepane

المردود 70.0%

المذيبات

methylene chloride

methylene chloride

ظروف التفاعل

المعالجة

1. 1
   أخرىat 10° C.
2. 2
   ترشيحAfter 5 hours the mixture is filtered
3. 3
   غسيلthe celite is washed with methylene chloride (10×50 ml)
4. 4
   أخرىThe solvent is removed at reduced pressure
5. 5
   workup.ADDITIONThe residue is diluted with ether (200 ml)
6. 6
   ترشيحfiltered
7. 7
   أخرىthe ether is removed at reduced pressure
8. 8
   أخرىThe crude product (4.7 g) is chromatographed on SilicAR CC-7 (100 g) in hexane
9. 9
   غسيلElution with 20% ethyl acetate/hexane

الإجراء التجريبي

Dry celite (40 g) and 6,6-ethylenedioxy-2-(4'-hydroxybutyl)-2-methyloxepane (4.88 g, 0.0196 mol) in methylene chloride (100 ml) are added to a pyridine-chromium trioxide solution [prepared from pyridine (18.6 g, 0.0284 mol) and chromium trioxide (11.8 g, 0.118 mol)]in dry methylene chloride (500 ml) at 10° C. in a nitrogen atmosphere. After 5 hours the mixture is filtered and the celite 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 ether is removed at reduced pressure. The crude product (4.7 g) is chromatographed on SilicAR CC-7 (100 g) in hexane. Elution with 20% ethyl acetate/hexane gives 6,6-ethylenedioxy-2-methyl-2-(4'-oxobutyl)-oxepane (14) as a clear colorless oil (3,3 g, 70%): ir (neat) 1725 cm-1 (CHO).

المصدر