HCID 14154617, compound → HCID 67897690, compound

HRID 2108221Notes

Reaction equation

HRID 2108221 reaction equation
[CH2:1]([Li])[CH2:2]CC.[CH2:6]([O:13][C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][C:15]=1[C:20](=O)[C:21]([O:23][CH3:24])=[O:22])[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1>CCCCCC.[Br-].C([P+](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)C.O1CCCC1>[CH2:6]([O:13][C:14]1[CH:19]=[CH:18][CH:17]=[CH:16][C:15]=1/[C:20](=[CH:1]\[CH3:2])/[C:21]([O:23][CH3:24])=[O:22])[C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1

Participants

6

Reactant 2

HCID 14154617HCID 14154617, compoundHCID 178418339Butyllithium

Product 1

HCID 67897690HCID 67897690, compoundYield 57%

Reagents, catalysts & solvents 3

HCID 73727Phosphonium, ethyltriphenyl-, bromide (1:1)CatalystHCID 8028TetrahydrofuranSolvent2×HCID 8058HexaneSolvent

Procedure

At 0° C. and under nitrogen, 32 ml (50 mmol) of a 1.6 molar solution of n-butyllithium in hexane is slowly added to 18.5 g (50 mmol) of ethyltriphenylphosphonium bromide in 100 ml of absolute tetrahydrofuran. After the mixture has been stirred for 30 minutes, 13.5 g (50 mmol) of methyl 2-(benzyloxy)-phenylglyoxylate in 25 ml of absolute tetrahydrofuran is dripped in at 0° C. The mixture is stirred for 16 hours at room temperature. After concentration, the residue is taken up in dichloromethane and washed several times with water. After drying over Na2SO4 the solvent is evaporated off. The crude product obtained is purified by chromatography (a 9:1 mixture of cyclohexane and ethyl acetate). There is obtained 8.0 g (57%) of the methyl crotonate (trans:cis ratio=9:1) as an oil.

Workup

  1. customis dripped in at 0° C
  2. stirringThe mixture is stirred for 16 hours at room temperature
  3. concentrationAfter concentration
  4. washwashed several times with water
  5. dry with materialAfter drying over Na2SO4 the solvent
  6. customis evaporated off
  7. customThe crude product obtained
  8. customis purified by chromatography (
  9. additiona 9:1 mixture of cyclohexane and ethyl acetate)

Sources & evidence

ORD record
ord-c91f6f985216425c9d297ceb5525ca99
Source dataset
uspto-grants-1990_06
Patent number
US04937372

Reaction notes

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