反応 #56555

ord-d66dda7157794b6691b8f2df3a19cc62

反応条件

詳細条件
See reaction.notes.procedure_details.

後処理

  1. 1
    その他A solution was prepared
  2. 2
    温度the reaction was refluxed for three hours
  3. 3
    抽出was extracted several times with ether
  4. 4
    洗浄washed with saturated aqueous sodium chloride solution
  5. 5
    乾燥dried over magnesium sulfate
  6. 6
    濃縮concentrated by solvent removal at the rotary evaporator
  7. 7
    その他The residue was further purified by chromatography on silica gel
  8. 8
    洗浄Elution with hexane

実験手順

A solution was prepared by dissolving titanium tetrachloride (1.10 ml, 10.0 mmol) in 25 ml tetrahydrofuran under an inert atmosphere. Calcium hydride (420 mg, 10.0 mmol) was added, and the resulting solution was stirred for two hours at room temperature. A solution of retinal, (1.42 gm, 5.0 mmol) in 5 ml dry tetrahydrofuran was then added, and the reaction was refluxed for three hours. After this, the solution was poured into 50 ml 2 N aqueous hydrochloric acid, and was extracted several times with ether. The ether extracts were combined, washed with saturated aqueous sodium chloride solution, dried over magnesium sulfate, and concentrated by solvent removal at the rotary evaporator. The residue was further purified by chromatography on silica gel. Elution with hexane gave 1.0 gm (75%) beta-carotene, identified by thin-layer chromatographic comparison with an authentic sample, and by its melting point, mp 180°-182°.

出典

DOI: 10.6084/m9.figshare.5104873.v1特許: US04225734uspto-grants-1980_09