Total Synthesis of (-)-N-Methylwelwitindolinone B Isothiocyanate.

The asymmetric synthesis of (-)-N-methylwelwitindolinoneB isothiocyanate is reported. Critical challenges overcome through these studies include the stereoselective installation of the sterically congested C13 alkyl chloride and control of the wayward reactivity of the indole unit to standard oxidants. A Pt-catalyzed hydrosilylation helped stymie unwanted rearrangements facilitated by vinyl group participation during the chloride installation step, and a new Fe-II-catalyzed oxidation accomplished the problematic conversion of indole into 2-indolinone.