Reaktion #1993395

Reaktionsgleichung

hydrochloric acid

water

ester

rac-[[2-[6-(4-acetyl-3-hydroxy-2-propylphenoxy)-hexyl]-3,4-dihydro-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-7-yl]oxy]acetic acid methyl ester

sodium hydroxide

water

→

yellow solid

Ausbeute 96.9%

rac.-[[2-[6-(4-acetyl-3-hydroxy-2-propylphenoxy)hexyl]-3,4-dihydro-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-7-yl]oxy]acetic acid

Ausbeute 96.9%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   ExtraktionThe mixture was extracted 3 times with ether
2. 2
   WaschenThe combined ether extracts were washed with 3 portions of saturated aqueous sodium bicarbonate
3. 3
   WaschenEach bicarbonate wash
4. 4
   Extraktionwas back-extracted with ether
5. 5
   ExtraktionThe acidic mixture was extracted 3 times with ethyl acetate
6. 6
   Waschenwashed with water and brine
7. 7
   Trocknendried (magnesium sulfate)
8. 8
   Filtrationfiltered
9. 9
   Einengenconcentrated in vacuo

Vorschrift

A solution of 1.1 g of the ester product from Example 5 and 0.966 g of sodium hydroxide, in 36 ml of methanol and 9 ml of water was stirred at room temperature for 5.5 hours then poured into 60 ml of cold 1N hydrochloric acid and 150 ml of water. The mixture was extracted 3 times with ether. The combined ether extracts were washed with 3 portions of saturated aqueous sodium bicarbonate. Each bicarbonate wash was back-extracted with ether. The bicarbonate washes were combined and acidified to pH 1 with 3N hydrochloric acid. The acidic mixture was extracted 3 times with ethyl acetate. The ethyl acetate extracts were combined, washed with water and brine, dried (magnesium sulfate), filtered and concentrated in vacuo to yield 1.04 g of a yellow solid. This material was recrystallized from acetonitrile giving 0.82 g (76.6%) of rac.-[[2-[6-(4-acetyl-3-hydroxy-2-propylphenoxy)hexyl]-3,4-dihydro-2-methyl-4-oxo-8-propyl-2H-1-benzopyran-7-yl]oxy]acetic acid as a colorless solid, m.p. 120.5°-125.0° C.

Quelle