Ethylene Glycol → 6-Bromo-1,4-dioxaspiro[4.6]undecane

HRID 903

反応式

HRID 903 の反応式
[Br:1]Br.[C:3]1(=[O:10])[CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][CH2:4]1.[CH2:11]([OH:14])[CH2:12]O.C(=O)(O)[O-].[Na+]>O1CCCC1>[CH2:11]1[O:14][C:3]2([CH2:9][CH2:8][CH2:7][CH2:6][CH2:5][CH:4]2[Br:1])[O:10][CH2:12]1

参加物

6

反応物 4

HCID 174Ethylene GlycolHCID 10400CycloheptanoneHCID 24408BromineHCID 516892Sodium Bicarbonate

生成物 1

HCID 2882266-Bromo-1,4-dioxaspiro[4.6]undecane

試薬・触媒・溶媒 1

HCID 8028Tetrahydrofuran溶媒

実験手順

Bromine (44.8 g, 0.28 mol) was added dropwise to a stirred solution of cycloheptanone (28.5 g, 0.25 mol) in a 1:1 solution (300 mL) of ethylene glycol and tetrahydrofuran at room temperature. The mixture was stirred for 5 hours, then poured into aqueous sodium bicarbonate and extracted 3× with diethyl ether. The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo to give 2-bromocycloheptanone ethylene ketal (60 g). A mixture of this crude bromo ketal and a methanolic solution of sodium methoxide (250 mL, 25 wt. % solution) was heated at reflux overnight. The mixture was cooled to ambient temperature, poured into water, and extracted with hexanes. The organic layer was washed with brine, dried over sodium sulfate, filtered, and concentrated in vacuo to afford 2-cycloheptenone ethylene ketal (39 g).

後処理

  1. extractionextracted 3× with diethyl ether
  2. washThe combined organic layers were washed with brine
  3. dry with materialdried over sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo

出典と根拠

ORDレコード
ord-c3c99a608b9c4984be003f74893691b4
出典データセット
uspto-grants-1998_03
特許番号
US05723462

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