Cornforth reagent → HCID 11427434, compound

HRID 455769Notes

Reaction equation

HRID 455769 reaction equation
[OH:1][CH2:2][C:3]([CH3:22])([CH3:21])[CH2:4][CH2:5][CH2:6][C:7](=[O:20])[CH2:8][CH2:9][CH2:10][CH2:11][C:12]([CH3:19])([CH3:18])[C:13]([O:15][CH2:16][CH3:17])=[O:14].[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=[O:24].[NH+]1C=CC=CC=1.[NH+]1C=CC=CC=1>CN(C=O)C.S(=O)(=O)(O)O.O>[CH2:16]([O:15][C:13](=[O:14])[C:12]([CH3:19])([CH3:18])[CH2:11][CH2:10][CH2:9][CH2:8][C:7](=[O:20])[CH2:6][CH2:5][CH2:4][C:3]([CH3:21])([CH3:22])[C:2]([OH:24])=[O:1])[CH3:17]

Participants

6

Reactant 2

HCID 2724130Cornforth reagentHCID 11243945HCID 11243945, compound

Product 1

HCID 11427434HCID 11427434, compoundYield 82%

Reagents, catalysts & solvents 3

HCID 962WaterSolventHCID 1118Sulfuric AcidSolventHCID 6228DimethylformamideSolvent

Procedure

A mixture of ethyl 12-hydroxy-2,2,11,11-tetramethyl-7-oxo-dodecanoate (3.26 g, 10 mmol) and pyridinium dichromate (14.0 g, 36 mmol) in DMF (45 mL) was stirred at room temperature for 46 h. The solution was diluted with 48% aqueous sulfuric acid (30 mL) and water (300 mL). The product was extracted with ethyl acetate (5×100 mL). The combined organic layers were washed with saturated NaCl solution (5×100 mL), dried over MgSO4, and concentrated to give the crude product (3.19 g) as a green oil. The crude product (3.1 g) was subjected to column chromatography on silica gel eluting with hexanes/ethyl acetate (3:1, then 2:1) to give pure 2,2,11,11-tetramethyl-7-oxo-dodecanedioic acid 1-ethyl ester (2.69 g, 82%) as a pale yellow oil. 1H NMR (300 MHz, CDCl3/TMS): δ (ppm): 11.30 (br. s, 1H), 4.10 (q, 2H, J=7.2 Hz), 2.39 (t, 4H, J=7.2 Hz), 1.56-1.48 (m, 8H), 1.24 (t, 5H, J=7.2 Hz), 1.20 (s, 6H), 1.15 (s, 6H). 13C NMR (75 MHz, CDCl3/TMS): δ (ppm): 210.9, 184.4, 178.1, 60.4, 43.1, 42.7, 42.2, 40.5, 39.8, 25.3, 25.0, 24.7, 24.3, 19.3, 14.4. HRMS (LSIMS, gly): Calcd. for C18H33O5 (MH+): 329.2328. found: 329.2330.

Workup

  1. extractionThe product was extracted with ethyl acetate (5×100 mL)
  2. washThe combined organic layers were washed with saturated NaCl solution (5×100 mL)
  3. dry with materialdried over MgSO4
  4. concentrationconcentrated
  5. customto give the crude product (3.19 g) as a green oil

Sources & evidence

ORD record
ord-372e78fed7124f918397a1a3543398d7
Source dataset
uspto-grants-2013_07
Patent number
US08497301B2

Reaction notes

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