Li-Jing Wang

Electrophilic Carbocyclization of Aryl Propargylic Alcohols: A Facile Synthesis of Diiodinated Carbocycles and Heterocycles

Diiodinated carbocycles and oxygen heterocycles can be readily synthesized by electrophilic carbocyclization of aryl propargylic alcohols in moderate to good yields under mild conditions. The resulting diiodide can be further exploited by subsequent oxidizing and coupling reactions. Both the iodine anion and cation generated from I(2) are used effectively. The presence of a trace amount of water is essential for this electrophilic cyclization.

Synthesis of polycyclic substituted vinylarenes via a one-pot intramolecular aryl alkylation–N-tosylhydrazone insertion reaction

A novel method of a palladium-catalyzed/norbornene-mediated intramolecular C-H activation/N-tosylhydrazones insertion reaction is developed. In this process, various bicyclic or tricyclic substituted vinylarenes are obtained with high efficiency under mild conditions.

Brønsted Acid Catalyzed and NIS-Promoted Cyclization of Diynones: Selective Synthesis of 4-Pyrone, 4-Pyridone, and 3-Pyrrolone Derivatives

Brønsted acid catalyzed tandem cyclization was found to be highly effective for the preparation of a series of polysubstituted 4-pyrones from diynones (yield up to 99%). 4-Pyridone and 3-pyrrolone derivatives were also selectively synthesized by employing NIS and/or Brønsted acid. NIS as an electrophilic reagent could promote these reactions efficiently and rapidly under very mild reaction conditions.

Gold-Catalyzed Tandem [3,3]-Propargyl Ester Rearrangement Leading to (E)-1H-Inden-1-ones

An efficient method for the synthesis of (E)-1H-inden-1-ones using gold-catalyzed tandem [3,3]-propargyl ester rearrangement followed by Michael addition under mild reaction conditions has been developed. The resulting products are important frameworks found in numerous natural products and pharmaceutically active compounds, as well as being valuable intermediates in organic synthesis.

Highly regioselective synthesis of 1,3-diiodonaphthalene derivatives via a sequential cascade iodocyclization.

A novel and flexible sequentially cascade iodocyclization for the synthesis of highly substituted 1,3-diiodinated naphthalene derivatives in up to 99% yield under mild conditions is reported. The dihalogenated moiety can be readily introduced into the naphthalenes in a position that is usually not easily functionalized.

Facile synthesis of 2-iodo-spiro[indene-1,1′-isobenzofuran]-3′-ones via iodine-promoted cascade cyclization

A novel and efficient synthetic approach to substituted 2-iodo-spiro[indene-1,1-isobenzofuran]-3-ones has been developed via an iodine-promoted cascade cyclization of 2-(3-hydroxy-3,3-diarylprop-1-yn-1-yl)benzoates. This sequential cascade process is concisely conducted at room temperature. Subsequent palladium-catalyzed Sonogashira, Suzuki, and Heck reactions of the resulting iodides proceed smoothly in good yields.

Facile Synthesis of Halogenated Spiroketals via a Tandem Iodocyclization

A strategy for the synthesis of spiroketal compounds through a tandem iodocyclization of 1-(2-ethynylphenyl)-4-hydroxybut-2-yn-1-one derivatives is presented. This reaction could proceed under very mild conditions in a short time and avoid the use of expensive and toxic metal catalysts. Moreover, the resulting halides can be further exploited by subsequent palladium-catalyzed coupling reactions, which act as the important intermediates for building other valuable compounds.

Synthesis of 3,4-Dihalogenated Furan-2-(5H)-ones by Electrophilic Cyclization of 4-Hydroxy-2-alkynoates

Functionalized 3,4-dihalogenated furan-2(5H)-ones can be readily prepared in moderate to good yields by treating 4-hydroxy-4-arylbut-2-ynoate derivatives with ICl, IBr, and I(2). Both halogen atoms of the electrophile are incorporated in the product. The resulting halides can further afford polycyclic aromatic compounds using known palladium-catalyzed coupling reactions.

Palladium-Catalyzed Construction of Tetracyclic Scaffolds via the 1,7-Enyne Carbocyclization/Iodophenol Dearomatization Cascade

An efficient palladium-catalyzed dearomatizing [2+2+1] carbocyclization of 1,7-enynes with iodophenols has been developed. A type of tetracyclic scaffold was built in this reaction, exhibiting a broad substrate scope with moderate to excellent yields. More importantly, this method provides a potential strategy for the synthesis of tetracyclic skeleton natural products.