Reaktion #592594

Reaktionsgleichung

ammonia

diethylether

4-methyl-2-(trityl-amino)-picolinic acid methyl ester

compound B1

4-methyl-2-(trityl-amino)-picolinic acid methyl ester

diisobutylaluminium hydride

→

4-Methyl-2-(trityl-amino)-picolinaldehyde

Lösungsmittel

acetic acid

toluene acetone

toluene

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   FiltrationThe colorless precipitate is filtered off with suction
2. 2
   Waschenwashed with toluene
3. 3
   ExtraktionThe filtrate is extracted with brine
4. 4
   Sonstigethe organic phase is dried
5. 5
   Einengenconcentrated to dryness
6. 6
   SonstigeAfter purification of the crude product
7. 7
   Sonstigeon silica gel (eluent: toluene/ethyl acetate 20:1) and evaporation of the eluents, 0.438 g of the title compound
8. 8
   Sonstigeare obtained as a colorless, amorphous solid

Vorschrift

A solution of 1.0 g of 4-methyl-2-(trityl-amino)-picolinic acid methyl ester (compound B1) in 35 ml of dry toluene is treated dropwise at −70° C. with 2.9 ml of a 1.5 M solution of diisobutylaluminium hydride in toluene. After 0.5 h 5 ml of diethylether and 2.9 ml of diluted aqueous acetic acid (20% strength) are added. After further 0.5 h the reaction mixture is warmed to room temperature and 29 ml of an aqueous solution of ammonia (25% strength) are added. The colorless precipitate is filtered off with suction and washed with toluene. The filtrate is extracted with brine, the organic phase is dried using sodium sulfate and concentrated to dryness. After purification of the crude product on silica gel (eluent: toluene/ethyl acetate 20:1) and evaporation of the eluents, 0.438 g of the title compound are obtained as a colorless, amorphous solid. M.p. 213° C. MS: 379.1 (MH+). TLC: Rf=0.66 (toluene/acetone 10:1).

Quelle