Boron trifluoride etherate → Lergotrile

Participants

Reaction Steps

810 mg. of D-6-methyl-8-cyanomethylergoline were suspended in 50 ml. acetonitrile and the suspension cooled to -5° to 0° C. 1.25 ml. of boron trifluoride etherate were added thus solubilizing the ergoline. Next, a solution of 0.27 ml. of sulfuryl chloride in 20 ml. of methylene dichloride was added in dropwise fashion. The reaction mixture was stirred and cooled for 30 minutes, then diluted with ammonium hydroxide. The diluted solution was extracted with a chloroform-isopropanol 3:1 solvent mixture. The organic layer was separated, washed with a saturated aqueous sodium chloride solution, dried and the solvent evaporated. The residue comprising lergotrile formed in the above chlorination procedure was chromatographed over fluorosil using chloroform containing 2 percent methanol as the eluant; 660 mg. of lergotrile were obtained melting at 268°-271° C. (with decomposition), 72 percent yield.

Provenance & Evidence