Rapid access to spirocyclized indolenines via palladium-catalyzed cascade reactions of tryptamine derivatives and propargyl carbonate

We report the intermolecular palladium-catalyzed reaction of tert-butyl propargyl carbonate with tryptamine derivatives or other indole-containing bis-nucleophiles. The reaction proceeds under mild conditions and with low catalyst loadings to afford novel spiroindolenine products in good to high yields.