Lysergic Acid → ((8beta)-9,10-Didehydro-6-methylergolin-8-yl)(1-pyrrolidinyl)methanone

Participants

Reaction Steps

30 g (111.80 mmol) lysergic acid is dissolved in 400 ml dichloromethane and cooled to 0°-5° C., 31.16 ml (223.61, 2 eq.) triethylamine and 18.66 ml (223.61 mmol, 2 eq.) pyrrolidine is added and within 15 minutes 1.5 equivalents propanephosphonic acid anhydride (50% in ethyl acetate). The reaction mixture is stirred for 1 hour at room temperature, then it is poured onto ice and extracted with dichloromethane, the organic layer is dried with Na2SO4, evaporated and the residue (28.6 g) is purified by chromatography on silica eluting with dichloromethane:methanol 9:1 to give ((6aR,9R)-7-Methyl-4,6,6a,7,8,9-hexahydro-indolo[4,3-fg]quinolin-9-yl)-pyrrolidin-1-yl-methanone.

Provenance & Evidence