Acetone → (R)-3-(N-Isopropylamino)-5-methoxychroman

HRID 1684306

Reaktionsgleichung

Reaktionsgleichung von HRID 1684306
[CH:1]([NH:4][CH:5]1[CH2:14][C:13]2[C:8](=[CH:9][CH:10]=[CH:11][C:12]=2[O:15][CH3:16])[O:7][CH2:6]1)([CH3:3])[CH3:2].CC1C=CC(C(O[C@H](C(O)=O)[C@H](OC(C2C=CC(C)=CC=2)=O)C(O)=O)=O)=CC=1.C(O)C.CC(C)=O>CCOCC.[OH-].[K+]>[CH:1]([NH:4][C@@H:5]1[CH2:14][C:13]2[C:8](=[CH:9][CH:10]=[CH:11][C:12]=2[O:15][CH3:16])[O:7][CH2:6]1)([CH3:3])[CH3:2]

Komponenten

6

Reaktionsbedingungen

Temperatur
20 °C

Versuchsvorschrift

The racemic 3-(N-isopropylamino)-5-methoxychroman (IV; 54 g, 0.224 mol) was mixed with an equimolar amount of (+)-di-1,4-toluoyl-D-tartaric acid (98.6 g, 0.244 mol). The mixture was dissolved in boiling ethanol (170 mL)/acetone (70 mL). The salt started to crystallize in the hot solvent mixture but was not filtered off until the solvent had cooled down to room temperature (20° C.). The salt was then recrystallized nine times from ethanol/acetone (1:5) to give the pure diastereomeric salt. Yield: 35% (54 g) (99% e.e). Mp: 166°-168° C. The free enantiomer as the base (R)-3-(N-isopropylamino)-5-methoxychroman was obtained by the extraction of the salt in ether/KOH (1M). Yield: 32%, 17.5 g, [α]D21 =-32° (C=0.1;MeOH). Mp. 285°-286° C. (HCl-salt)

Aufarbeitung

  1. dissolutionThe mixture was dissolved
  2. customto crystallize in the hot solvent mixture
  3. filtrationwas not filtered off until the solvent
  4. customThe salt was then recrystallized nine times from ethanol/acetone (1:5)
  5. customto give the pure diastereomeric salt

Quellen und Nachweise

ORD-Eintrag
ord-7da7b27c57614c45af48ab1803401f64
Quelldatensatz
uspto-grants-1997_06
Patentnummer
US05639784

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