1-Ethyl-4-hydroxy-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic Acid Methyl Ester → HCID 13911142, Verbindung

Temperatur

-78 °C

To a solution of 1-ethyl-4-hydroxy-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic acid methyl ester (1 g, 3.6 mmol) in 60 mL of dry methylene chloride at -78° C. under nitrogen was added TiCl4 in one portion and then after ~10 minutes, a solution of benzyl magnesium bromide in ether was added in one portion and the reaction mixture was allowed to stir at -78° C. for ~30 minutes. The reaction was quenched with methanol (3 mL) at -78° C. and then poured into water (10 mL). The two layers were separated and the aqueous layer was then extracted with methylene chloride (2×100 mL), dried over magnesium sulfate and concentrated in vacuo. The crude product was passed through a pad of silica gel, eluting with 10% EtOAc in hexane to give 0.67 g (51.5%) of the product as an oil, which had isomer ratio of 75:25 by HPLC.

1. waitafter ~10 minutes
2. customThe reaction was quenched with methanol (3 mL) at -78° C.
3. additionpoured into water (10 mL)
4. customThe two layers were separated
5. extractionthe aqueous layer was then extracted with methylene chloride (2×100 mL)
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated in vacuo
8. washeluting with 10% EtOAc in hexane

ORD-Eintrag

ord-3c249d2ea45e4d7eb9c39839b84aa498

Quelldatensatz

uspto-grants-1987_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04686213