Zi-Sheng Chen

One-Pot Access to Indolo[2,3-b]quinolines by Electrophile-Triggered Cross-Amination/Friedel-Crafts Alkylation of Indoles with 1-(2-Tosylaminophenyl)ketones

Activation of C2 and C3 of indoles by molecular iodine (I(2)) and base followed by in situ reaction with 1-(2-tosylaminophenyl)ketones or 2-tosylaminobenzaldehyde can afford highly substituted indolo(2,3-b)quinolines in moderate to excellent yields (up to 99%). The reaction provides a metal-free selective difunctionalization of indoles. The synthetic potential of the protocol has been illustrated by the synthesis of neocryptolepine and its 11-methyl analogue.

Gold-Catalyzed Oxidation Terminal Alkyne: An Approach to Synthesize Substituted Dihydronaphthalen-2(1H)-ones and Phenanthrenols

A facile gold-catalyzed oxidation terminal alkynes to synthesize substituted dihydronaphthalen-2(1H)-ones 3 and phenanthrenols 5 was realized. Various useful structures and drug precursors were generated in up to 99% yield under mild condition and low catalyst loading.

Gold(III)-Catalyzed Regioselective Oxidation/Cycloisomerization of Diynes: An Approach to Fused Furan Derivatives

The first gold(III)-catalyzed regioselective oxidation/cycloisomerization of diynes 1 with pyridine N-oxide as the oxidant was developed, providing a range of synthetically valuable and useful fused furan derivatives 3 in moderate to good yields. Control experiments and the confirmation structure of minor products 5 suggest that this chemistry was a concerted gold(III)-catalyzed oxidation/SN2-type addition/cyclization process via a β-gold vinyloxypyridinium intermediate and a putative vinyl cation intermediate.