Hexamethylphosphoramide → Dibenzyl 2-methylenepentanedioate

HRID 1976707Notes

Reaction equation

HRID 1976707 reaction equation
[C:1]([O:5][CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)(=[O:4])[CH:2]=[CH2:3].CN(P(N(C)C)(N(C)C)=O)C>>[CH2:3]=[C:2]([CH2:3][CH2:2][C:1]([O:5][CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)=[O:4])[C:1]([O:5][CH2:6][C:7]1[CH:12]=[CH:11][CH:10]=[CH:9][CH:8]=1)=[O:4]

Participants

3

Reactant 2

HCID 12679HexamethylphosphoramideHCID 75617Benzyl acrylate

Product 1

HCID 10947302Dibenzyl 2-methylenepentanedioateYield 92.5%

Procedure

Benzyl acrylate (500 g, 3.0 mol) was heated in an oil bath to 100° C. Heating was stopped and HMPT (10 g, 61 mmol) was added dropwise while maintaining an internal temperature below 140° C. Once addition was complete, the mixture was stirred and cooled to room temperature. A slurry of silica (5:1 Hexane/EtOAc) was added and the mixture was placed in a column containing a plug of dry silica. The column was washed with 1:1 Hexane/EtOAc and the fractions were combined and evaporated to give 450 g of clear light golden liquid. The liquid was distilled under high vacuum (200 μHg) at 185° C. to give 212 g (4%) of a clear and colorless liquid. 1H NMR (CDCl3): 7.3 ppm (m, 10H), 6.2 ppm (s, 1H), 5.6 ppm (s, 1H), 5.2 ppm (s, 2H), 5.1 ppm (s, 2H), 2.6 ppm (m, 4H).

Workup

  1. temperatureHeating
  2. temperaturewhile maintaining an internal temperature below 140° C
  3. additionOnce addition
  4. additionA slurry of silica (5:1 Hexane/EtOAc) was added
  5. additioncontaining a plug of dry silica
  6. washThe column was washed with 1:1 Hexane/EtOAc
  7. customevaporated

Sources & evidence

ORD record
ord-299bfb1f1d6a4deeba2b349ae3b5daa3
Source dataset
uspto-grants-2001_05
Patent number
US06228888B1

Reaction notes

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