3-Chloro-2-chloromethyl-1-propene → Ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate

HRID 221970Notes

Reaction equation

HRID 221970 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([CH2:8][C:9]([O:11][CH2:12][CH3:13])=[O:10])=[CH:4][CH:3]=1.[Li+].C[Si]([N-][Si](C)(C)C)(C)C.[Cl:24][CH2:25][C:26]([CH2:28]Cl)=[CH2:27].C(=O)(O)[O-].[Na+]>C1COCC1>[Br:1][C:2]1[CH:3]=[CH:4][C:5]([CH:8]([CH2:28][C:26]([CH2:25][Cl:24])=[CH2:27])[C:9]([O:11][CH2:12][CH3:13])=[O:10])=[CH:6][CH:7]=1

Participants

6

Reactant 4

HCID 158593-Chloro-2-chloromethyl-1-propeneHCID 516892Sodium BicarbonateHCID 2733832Lithium HexamethyldisilazideHCID 7020609Ethyl 2-(4-bromophenyl)acetate

Product 1

HCID 59161543Ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a solution of ethyl (4-bromophenyl)acetate (143 g, 588 mmol) in THF (800 mL) was added LHMDS (1.13 eq in THF) at −78° C. After 30 minutes, the reaction mixture was added to a solution of 3-chloro-2-chloromethyl-1-propene (147 g, 1180 mmol) in THF (500 mL) at −78° C. via cannula. The reaction was allowed to slowly warm from −78° C. to rt over 15 hours. The reaction mixture was poured into sodium bicarbonate, extracted with EtOAc, dried over sodium sulfate, filtered and concentrated. The crude residue was purified by column chromatography eluting with 1-20% EtOAc/Hexane. The appropriate fractions were combined and the solvent removed in vacuo to give ethyl 2-(4-bromophenyl)-4-(chloromethyl)pent-4-enoate (1-1) as a clear oil. MS (M+H)+: 332.

Workup

  1. temperatureto slowly warm from −78° C. to rt over 15 hours
  2. extractionextracted with EtOAc
  3. dry with materialdried over sodium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated
  6. customThe crude residue was purified by column chromatography
  7. washeluting with 1-20% EtOAc/Hexane
  8. customthe solvent removed in vacuo

Sources & evidence

ORD record
ord-2fe2a5c6810a4b97933ac6b5f2bffc25
Source dataset
uspto-grants-2012_06
Patent number
US08207169B2

Reaction notes

Loading…