Ethyl alpha-(4-carbomethoxy-2-n-propylphenoxy)-3,4-methylenedioxyphenylacetate → 2-(Benzo[d][1,3]dioxol-5-yl)-2-(4-(methoxycarbonyl)-2-propylphenoxy)acetic acid

HRID 865521Notes

Reaction equation

HRID 865521 reaction equation
[C:1]([C:5]1[CH:26]=[CH:25][C:8]([O:9][CH:10]([C:16]2[CH:21]=[CH:20][C:19]3[O:22][CH2:23][O:24][C:18]=3[CH:17]=2)[C:11]([O:13]CC)=[O:12])=[C:7]([CH2:27][CH2:28][CH3:29])[CH:6]=1)([O:3][CH3:4])=[O:2]>CO>[C:1]([C:5]1[CH:26]=[CH:25][C:8]([O:9][CH:10]([C:16]2[CH:21]=[CH:20][C:19]3[O:22][CH2:23][O:24][C:18]=3[CH:17]=2)[C:11]([OH:13])=[O:12])=[C:7]([CH2:27][CH2:28][CH3:29])[CH:6]=1)([O:3][CH3:4])=[O:2]

Participants

3

Reactant 1

HCID 15383769Ethyl alpha-(4-carbomethoxy-2-n-propylphenoxy)-3,4-methylenedioxyphenylacetate

Product 1

HCID 153837702-(Benzo[d][1,3]dioxol-5-yl)-2-(4-(methoxycarbonyl)-2-propylphenoxy)acetic acidYield 94%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

A 1 L 3 necked 24/40 round bottom flask equipped with a mechanical stirrer, a dropping funnel, and a nitrogen inlet was charged with a solution of 76.3 g 0.185 mol) of the semi-purified product of Step A dissolved in 500 mL of methanol. The flask was purged with nitrogen, the stirrer was started, and 37 mL of a 5.0 N aqueous solution of sodium hydroxide was added over a 30 minute period via an addition funnel. The reaction mixture was stirred at room temperature for an additional 30 minutes at which point TLC analysis (CH2Cl2 --MeOH--NH4OH90:10:1) indicated that the starting material had been consumed. The reaction mixture was adjusted to pH=4 with 6 N HCl, and the bulk of the organic solvent was removed in vacuo. The precipitated organic product and the aqueous layer were next partitioned between CH2Cl2 (1 L) and water (1 L) which produced a copious emulsion. The reaction mixture was then aged overnight in a refridgerator which resulted in crystallization of the organic product. The crystalline solid was separated from the two phase mixture by filtration and washed with CH2Cl2. The solid was slurried again in diethylether, filtered, washed with hexane, and then dried in a vacuum to afford 65 g (94%) of the title compound as a white crystalline solid. 1H-NMR (400 MHz, CD3OD, ppm): δ0.93 (t, J=7.20 Hz, 3H), 1.62-1.75 (m, 2H), 2.63-2.70 (m, 1H), 2.77-2.81 (m, 1H), 3.84 (s, 3H), 5.54 (s, 1H), 5.94 (s, 2H), 6.81 (d, J=7.60 Hz, 1H), 6.89 (d, J=9.20 Hz, 1H), 7.08 (d, J=1.60 Hz, 1H), 7.11 (br s, 1H), 7.78-7.81 (m, 2H).

Workup

  1. customThe flask was purged with nitrogen
  2. addition37 mL of a 5.0 N aqueous solution of sodium hydroxide was added over a 30 minute period via an addition funnel
  3. customhad been consumed
  4. customthe bulk of the organic solvent was removed in vacuo
  5. customThe precipitated organic product and the aqueous layer were next partitioned between CH2Cl2 (1 L) and water (1 L) which
  6. customproduced a copious emulsion
  7. waitThe reaction mixture was then aged overnight in a refridgerator which
  8. customresulted in crystallization of the organic product
  9. customThe crystalline solid was separated from the two phase mixture by filtration
  10. washwashed with CH2Cl2
  11. filtrationfiltered
  12. washwashed with hexane
  13. customdried in a vacuum

Sources & evidence

ORD record
ord-a49c4398515f4df3a5e3992a56d800f2
Source dataset
uspto-grants-1996_10
Patent number
US05565485

Reaction notes

Loading…