Dimethyl Sulfoxide → Ethyl 4-(N-BOC-4-piperidyl)trans-crotonate

HRID 1742579Notes

Reaction equation

HRID 1742579 reaction equation
C(Cl)(=O)C(Cl)=O.CS(C)=O.[C:11]([N:18]1[CH2:23][CH2:22][CH:21]([CH2:24][CH2:25]O)[CH2:20][CH2:19]1)([O:13][C:14]([CH3:17])([CH3:16])[CH3:15])=[O:12].C(N(CC)CC)C.[C:34]([CH:39]=P(C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)([O:36][CH2:37][CH3:38])=[O:35]>C(Cl)Cl>[C:11]([N:18]1[CH2:19][CH2:20][CH:21]([CH2:24]/[CH:25]=[CH:39]/[C:34]([O:36][CH2:37][CH3:38])=[O:35])[CH2:22][CH2:23]1)([O:13][C:14]([CH3:15])([CH3:16])[CH3:17])=[O:12]

Participants

7

Reactant 5

HCID 679Dimethyl SulfoxideHCID 8471TriethylamineHCID 65578Oxalyl chlorideHCID 70670Acetic acid, 2-(triphenylphosphoranylidene)-, ethyl esterHCID 8541401-(tert-Butoxycarbonyl)-4-(2-hydroxyethyl)piperidine

Product 1

HCID 10017534Ethyl 4-(N-BOC-4-piperidyl)trans-crotonateYield 54.8%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a stirred solution of oxalyl chloride (0.43 mL, 5.0 mmol) in CH2Cl2 (20 mL) at -78° C. was added DMSO (0.52 ml, 7.0 mmol) dropwise. After gas evolution subsided (~5 minutes) the alcohol 17 (0.8 g, 3.5 mmol) in CH2Cl2 (20 mL) was added in a stream. After 20 minutes triethylamine (1.7 mL, 12 mmol) was added dropwise and then the cooling bath removed. After 20 minutes (carbethoxymethylene) triphenylphosphorane (1.4 g, 4.0 mmol) was added. After 2.0 hours the reaction mixture was diluted with petroleum ether and then washed sequentially with H2O, 5% KHSO4, and brine, dried (MgSO4) and concentrated. Flash chromatography (silica, 15% ethyl acetate/hexanes) gave the ester 18 (0.57 g) as a colorless oil.

Workup

  1. custom(~5 minutes)
  2. additionwas added in a stream
  3. customthe cooling bath removed
  4. washwashed sequentially with H2O, 5% KHSO4, and brine
  5. dry with materialdried (MgSO4)
  6. concentrationconcentrated

Sources & evidence

ORD record
ord-5a8b1d1030bd4ad48bdec6f634f6e4af
Source dataset
uspto-grants-1994_08
Patent number
US05340798

Reaction notes

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