Reaktion #5995

Reaktionsgleichung

diester

(RS)-5-[(4-Carbomethoxyphenyl)methoxy]-2-(diphenyl acetyl)-1,2,3,4-tetrahydro-6-methoxy-3-isoquinolinecarboxylic acid, ethyl ester

→

(RS)-5-(4-Carboxyphenylmethoxy)-2-(diphenylacetyl) -1,2,3,4-tetrahydro-6-methoxy-3-isoquinolinecarboxylic acid

Lösungsmittel

methanol

methanol

sodium hydroxide

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.DISTILLATIONto distill off
2. 2
   workup.ADDITIONAfter 1 hour (pot temperature =90° C.), 1N hydrochloric acid (35 mL) is added
3. 3
   Sonstigeto precipitate a gum
4. 4
   workup.ADDITIONOn addition of 10 mL of ether, crystals
5. 5
   SonstigeRecrystallization from ethyl acetate petroleum ether
6. 6
   Sonstigegives pure product

Vorschrift

A solution of 1.10 g (0.0019 mole) of the diester from Example 32 in 100 mL of methanol and 15 mL of 2N sodium hydroxide is heated to the boiling point, allowing the methanol to distill off. After 1 hour (pot temperature =90° C.), 1N hydrochloric acid (35 mL) is added to precipitate a gum. On addition of 10 mL of ether, crystals develop; wt. 0.84 g. Recrystallization from ethyl acetate petroleum ether gives pure product; mp 190°-192° C.

Quelle