Triethylamine → ZK 91296

Participants

Reaction Conditions

Reaction Steps

10 mmol of 5-benzyloxy-4-methoxymethyl-1,2,3,4-tetrahydro-β-carboline-3-carboxylic acid ethyl ester is dissolved in 45 ml of methylene chloride. The solution is cooled to -15° C. and 4.6 ml of triethylamine is added Then a solution of 3.6 ml of tert-butyl hypochlorite in 45 ml of methylene chloride is added within about 10 minutes and stirred for 5 minutes more. After further addition of 3.8 ml of triethylamine, heating to ambient temperature and stirring at this temperature for 4 hours takes place. The solvent is distilled off in vacuum (bath temperature +30° C.) and condensed to dryness at +60° C. bath temperature. The residue is taken up in methylene chloride, filtered over silica gel, rewashed with methylene chloride, the product is eluted with ethyl acetate, the eluate is condensed and washed with ice water. The precipitate is filtered off and wahsed with ice-cold ethyl acetate. 2.93 g of 5-benzyloxy-4-methoxymethyl-β-carboline-3-carboxylic acid ethyl ester (80.5% of theory) with melting point 190.0° C. is obtained.

Provenance & Evidence