A NOVEL-APPROACH TO THE ERGOT ALKALOID SKELETON

We describe a ten stage synthesis of an advanced intermediate for elab oration into ergot alkaloids, from 4-carbomethoxyindole. The key step involved an intramolecular cyclisation involving the allyl cation deri ved from N-benzenesulphonyl, 3-(3'-methoxyprop-2'-en-1'-yl), y-2'trime thylsilylmethyl-prop-2'-en-1'-yl)-indole.