Reaktion #52356

Reaktionsgleichung

Intermediate 25

2-cyclopropyl-4,4-dimethyl-1,2,3,4-tetrahydroisoquinoline-6-carboxaldehyde

carbon tetrabromide

2-cyclopropyl-4,4-dimethyl-1,2,3,4-tetrahydroisoquinoline-6-carboxaldehyde

ethyl acetate

triphenyl phosphine

→

title compound

6-(2,2-Dibromo-vinyl)-2-cyclopropyl-4,4-dimethyl-1,2,3,4-tetrahydroisoquinoline

Lösungsmittel

dichloromethane

hexane

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITAfter 1.5 h between 0° C. and 10° C.

Vorschrift

A stirred, cooled (ice-bath) solution of triphenyl phosphine (0.53 g, 2 mmol) in anhydrous dichloromethane was treated with carbon tetrabromide (0.35 g, 1 mmol) under argon. After 0.5 h, a solution of 2-cyclopropyl-4,4-dimethyl-1,2,3,4-tetrahydroisoquinoline-6-carboxaldehyde (Intermediate 25, 0.13 g, 0.57 mmol) in dichloromethane (2 mL) was cannulated into the reaction mixture. After 1.5 h between 0° C. and 10° C., the reaction mixture was subjected to flash column chromatography over silica gel (230-400 mesh) using 3-5% ethyl acetate in hexane as the eluent to afford the title compound as a viscous, pale yellow oil (0.18 g, 82%).

Quelle