Ethyl Acetate → 5-(2-Benzyloxy-ethyl)-cyclohex-1-enecarboxylic acid methyl ester

HRID 2252948Notes

Reaction equation

HRID 2252948 reaction equation
[CH3:1][O:2][C:3]([CH:5]1[CH2:10][CH:9]([CH2:11][CH2:12][O:13][CH2:14][C:15]2[CH:20]=[CH:19][CH:18]=[CH:17][CH:16]=2)[CH2:8][CH2:7][CH:6]1O)=[O:4].O=S(Cl)Cl.C1CCN2C(=NCCC2)CC1.CCOC(C)=O>N1C=CC=CC=1>[CH3:1][O:2][C:3]([C:5]1[CH2:10][CH:9]([CH2:11][CH2:12][O:13][CH2:14][C:15]2[CH:16]=[CH:17][CH:18]=[CH:19][CH:20]=2)[CH2:8][CH2:7][CH:6]=1)=[O:4]

Participants

6

Reactant 4

HCID 8857Ethyl AcetateHCID 24386Thionyl ChlorideHCID 811841,8-Diazabicyclo(5.4.0)undec-7-eneHCID 235495395-(2-Benzyloxy-ethyl)-2-hydroxy-cyclohexanecarboxylic acid methyl ester

Product 1

HCID 235495385-(2-Benzyloxy-ethyl)-cyclohex-1-enecarboxylic acid methyl ester

Reagents, catalysts & solvents 1

HCID 1049PyridineSolvent

Procedure

A solution of 5-(2-benzyloxy-ethyl)-2-hydroxy-cyclohexanecarboxylic acid methyl ester (Intermediate R2, 0.72 g, 2.48 mmol) in pyridine (10 mL) was treated with SOCl2 (0.73 mL, 12.4 mmol) at −20 EC. The mixture was allowed to react for 15 m and was then warmed to 55 EC for 16 h. The solvents were removed under vacuum and the residue was diluted in ether at 0 EC. The solution was quenched with water, washed with 1M HCl, 5% NaOH and brine. The organic material was dried over MgSO4 filtered and freed of solvent. The mixture was diluted with benzene and water was removed by azeotropic distillation under vacuum. The residue was dissolved in benzene (15 mL) and DBU (0.76 mL, 5 mmol) was added. The mixture was reacted for 30 m at rt. After work-up and chromatography on SiO2 with 20% EtOAc:Hx 5-(2-benzyloxy-ethyl)-cyclohex-1-enecarboxylic acid methyl ester (Intermediate R3) was isolated 0.56 g (82%).

Workup

  1. customto react for 15 m
  2. temperaturewas then warmed to 55 EC for 16 h
  3. customThe solvents were removed under vacuum
  4. additionthe residue was diluted in ether at 0 EC
  5. customThe solution was quenched with water
  6. washwashed with 1M HCl, 5% NaOH and brine
  7. dry with materialThe organic material was dried over MgSO4
  8. filtrationfiltered
  9. additionThe mixture was diluted with benzene and water
  10. customwas removed by azeotropic distillation under vacuum
  11. dissolutionThe residue was dissolved in benzene (15 mL)
  12. customThe mixture was reacted for 30 m at rt

Sources & evidence

ORD record
ord-bc140e7aab5f4a97889f9e25d4ae479b
Source dataset
uspto-grants-2008_01
Patent number
US07323485B2

Reaction notes

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