Hydrogen Bromide → (+)-Cis-1-methyl-3-ethoxymethyl-4-(3,4-dichlorophenyl)-piperidine hydrobromide

(±)-Cis-1-methyl-3-ethoxymethyl-4-(3,4-dichlorophenyl)-piperidine (9) (1.1 g, 3.7 mmol) and (−)-dibenzoyltartaric acid (0.48 g, 1.3 mmol) were dissolved in 99% ethanol (10 ml) and evaporated to dryness. The evaporation residue was crystallized from toluene (3 ml). Recrystallized from a mixture of toluene (10 ml) and ethanol (10 ml). The precipitate was isolated and dissolved in a mixture of 4 N NaOH (5 ml) and diethyl ether (10 ml). The diethyl ether was separated and dried with magnesium sulfate yielding 0.25 g (45%) of the product as the free base. Hydrobromic acid (0.20 ml, 1.7 mmol) was added and the mixture evaporated to dryness. The residue was recrystallized from ethanol (2 ml) and diethyl ether (10 ml) to yield 0.20 g (28%) of (13), mp 183-185° C., [α]D25=+62.8°, (c=14 mg/ml in 99% ethanol).

1. customevaporated to dryness
2. customThe evaporation residue was crystallized from toluene (3 ml)
3. customRecrystallized from a mixture of toluene (10 ml) and ethanol (10 ml)
4. customThe precipitate was isolated
5. customThe diethyl ether was separated
6. dry with materialdried with magnesium sulfate yielding 0.25 g (45%) of the product as the free base
7. customthe mixture evaporated to dryness
8. customThe residue was recrystallized from ethanol (2 ml) and diethyl ether (10 ml)

ORD-Eintrag

ord-f57b696915a940bc855d76dd41447e00

Quelldatensatz

uspto-grants-2009_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07560562B2