Oxalic Acid → (Z)-3-(4-methoxyphenyl)-4-methyl-2-pentenal

HRID 2232798Notes

Reaction equation

HRID 2232798 reaction equation
C(N[CH:5]([CH3:7])C)(C)C.[CH2:8]([Li])[CH2:9][CH2:10][CH3:11].C(O)(=O)[C:14](O)=[O:15].[CH3:19][CH:20]([CH3:25])[CH:21]=[CH:22][CH:23]=[O:24]>CCCCCC.C(N=CC)(C)(C)C.ClP(=O)(OCC)OCC.O1CCCC1>[CH3:14][O:15][C:8]1[CH:7]=[CH:5][C:11](/[C:21](/[CH:20]([CH3:25])[CH3:19])=[CH:22]\[CH:23]=[O:24])=[CH:10][CH:9]=1

Participants

9

Reactant 4

HCID 971Oxalic AcidHCID 7912DiisopropylamineHCID 214582-Pentenal, 4-methyl-HCID 178418339Butyllithium

Product 1

HCID 22155343(Z)-3-(4-methoxyphenyl)-4-methyl-2-pentenal

Reagents, catalysts & solvents 4

HCID 8028TetrahydrofuranSolventHCID 8058HexaneSolventHCID 13139Diethyl chlorophosphateSolventHCID 138901N-Ethylidene-2-methylpropan-2-amineSolvent

Procedure

The compounds were prepared according to the procedure described in Example 84 except that the reaction was worked up after 3 days. The following reagents were used: 1-(4-methoxyphenyl)-2-methylpropanone (17.8 g), diisopropylamine (32.2 mL), 1.6M 1-butyl lithium in hexane (143 mL), acetaldehyde N-tert-butylimine (14.75 mL), diethyl chlorophosphonate (16.6 mL) and tetrahydrofuran (200 mL). The work up, varied only in that the oxalic acid hydrolysis was run overnight at room temperature, furnished 21.3 g of crude product containing (E)- and (Z)-3-4-methoxyphenyl)-4-methyl-2-pentenal in the ratio of 2:3. An attempt to separate the crude by HPLC (ether-hexane; 3:17; multiple recycles) only resulted in mixtures of (E)-3-(4-methoxphenyl)-4-methyl-2-pentenal and (Z)-3-(4-methoxyphenyl)-4-methyl-2-pentenal with E/Z ratios that varied between 1:and 1:1.

Workup

  1. customThe compounds were prepared
  2. waitwas run overnight at room temperature
  3. customfurnished 21.3 g of crude product
  4. customAn attempt to separate the crude by HPLC (ether-hexane; 3:17; multiple recycles)

Sources & evidence

ORD record
ord-be148e75924044948c2cda851d4cfbb9
Source dataset
uspto-grants-1988_11
Patent number
US04788206

Reaction notes

Loading…