Toluene → HCID 86643171, compound

Participants

Reaction Steps

(1R)-1-[(3,4-dimethoxyphenyl)methyl]-1,2,3,4-tetrahydro-6,7-dimethoxy-2-tert-butoxycarbonylethylisoquinoline oxalate (7.0 g, 0.0125 moles), prepared as described in example 1, was dissolved in water (50 ml) and 25% aqueous ammonium hydroxide solution was added to produce a pH in the range of 9-10. Toluene (100 ml) was added and the mixture was stirred for 15 minutes at ambient temperature. The upper organic layer was separated and washed with 10% sodium chloride solution. The organic layer was dried over magnesium sulfate and the solvent was evaporated under reduced pressure to afford a solid residue. Iodomethane (30 ml, 0.482 moles) was added to the residue and the mixture was stirred to obtain a solution and kept at ambient temperature overnight. The resulting precipitate was collected by filtration, washed with diethyl ether and dried at room temperature to afford a mixture of 81.5% of the cis and 18.5% of the trans isomers of (1R)-1-[(3,4-dimethoxyphenyl)methyl]-1,2,3,4-tetrahydro-6,7-dimethoxy-2-methyl-2-tert-butoxycarbonylethyl-isoquinolinium iodide (5.5 g; 72% yield).

Provenance & Evidence