Potassium tert-butoxide → 2-(4-Ethoxy-2,3-difluorophenyl)-5-vinylselenophene

HRID 1873397

Reaction equation

HRID 1873397 reaction equation
[CH3:1]C(C)([O-])C.[K+].[CH2:7]([O:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]2[Se:20][C:19]([CH:21]=O)=[CH:18][CH:17]=2)=[C:12]([F:23])[C:11]=1[F:24])[CH3:8]>[Br-].C[P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.C1COCC1.CC(OC)(C)C.O.Cl>[CH2:7]([O:9][C:10]1[CH:15]=[CH:14][C:13]([C:16]2[Se:20][C:19]([CH:21]=[CH2:1])=[CH:18][CH:17]=2)=[C:12]([F:23])[C:11]=1[F:24])[CH3:8]

Participants

8

Reactant 2

HCID 23665647Potassium tert-butoxideHCID 594563155-(4-Ethoxy-2,3-difluorophenyl)selenophene-2-carbaldehyde

Product 1

HCID 594563452-(4-Ethoxy-2,3-difluorophenyl)-5-vinylselenophene

Reagents, catalysts & solvents 5

HCID 74505Methyltriphenyliphosphonium bromideCatalystHCID 313Hydrochloric AcidSolventHCID 962WaterSolventHCID 8028TetrahydrofuranSolvent2×HCID 15413tert-Butyl methyl etherSolvent

Procedure

3.0 g (8.4 mmol) of methyltriphenylphosphonium bromide are initially introduced in 50 ml of THF at 0° C., and 0.89 g (7.9 mmol) of potassium tertbutoxide is dissolved in 7 ml of THF is added. After 1.5 h at RT, 2.0 g (6.4 mmol) of 5-(4-ethoxy-2,3-difluorophenyl)selenophene-2-carbaldehyde are added, and the batch is stirred for 2.5 h. The mixture is diluted with MTBE, and water and 2 N hydrochloric acid are added. The organic phase is separated off, and the aqueous phase is extracted with MTBE. The combined organic phases are washed with sat. sodium chloride soln. and dried using sodium sulfate. The solution is concentrated to dryness, and the residue is purified by column chromatography (SiO2, n-heptane:EtOAc=10:1→5:1). Further purification is carried out by recrystallisation from n-heptane; 2-(4-ethoxy-2,3-difluorophenyl)-5-vinylselenophene is obtained as a yellow-orange solid.

Workup

  1. additionis added
  2. additionare added
  3. customThe organic phase is separated off
  4. extractionthe aqueous phase is extracted with MTBE
  5. washThe combined organic phases are washed with sat. sodium chloride soln
  6. customand dried
  7. concentrationThe solution is concentrated to dryness
  8. customthe residue is purified by column chromatography (SiO2, n-heptane:EtOAc=10:1→5:1)
  9. customFurther purification
  10. customis carried out by recrystallisation from n-heptane

Sources & evidence

ORD record
ord-fe73d39bd56242818070e29deecf8535
Source dataset
uspto-grants-2012_11
Patent number
US08304036B2

Linked notes

Loading…