Mei-Jin Zhong

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.

Zinc-Catalyzed [4+3] Cycloaddition with Concomitant Furan Annulation: Formation of Cyclohepta[b]Furans

A convenient zinc-promoted [4+3] cycloaddition of a carbonyl ene-yne with simple dienes was first achieved. This reaction provided an efficient strategy to prepare various cyclohepta[b]furan rings by cascade cycloadditions. Additionally, a multicomponent reaction of dione, alkynal, and diene was also reported, which exhibited a novel strategy for selective creations of C-O bonds and C-C bonds.

Bi(III)-Catalyzed Intermolecular Reactions of (Z)-Pent-2-en-4-yl Acetates with Ethynylarenes for the Construction of Multisubstituted Fluorene Skeletons through a Cascade Electrophilic Addition/Cycloisomerization Sequence

A Bi(III)-catalyzed method for the synthesis of highly conjugated aromatic multisubstituted fluorene with (Z)-pent-2-en-4-yl acetates and ethynylarenes via domino reaction is described. In this process, the reaction appears to be very general and suitable for a variety of multisubstituted fluorene.

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 tetrasubstituted cyclopentadienes via palladium-catalyzed reaction of (Z)-2-en-4-yn acetates and N-methyl indoles.

An efficient approach for the synthesis of tetrasubstituted cyclopentadienes through Pd-catalyzed reactions of (Z)-2-en-4-yn acetates with substituted indoles was developed. This methodology has the advantages of broad scope, simple conditions and easily accessible starting materials.

Copper-catalyzed dimerization fragmentation cyclization reactions of (E)-1-en-4-yn-3-ols as a versatile approach for the synthesis of multisubstituted 1H-cyclopenta[b]naphthalenes

An intermolecular condensation reaction of 1,3,5-triarylenynols catalyzed by copper is developed. This reaction is a straightforward method for the synthesis of highly conjugated 1H-cyclopenta[b]naphthalene. Fluorescent properties have been determined for some of the products.

Synthesis of (E)-3-styryl-2,5-dihydro-1H-pyrrole derivatives via Pd-catalyzed addition of indoles to hydroxy 1,6-enynes

A mild Pd-catalyzed addition of indoles to hydroxy 1,6-enynes has been developed. In this reaction, hydroxy 1,6-enynes were selectively transformed into (E)-3-styryl-2,5-dihydro-1H-pyrrole derivatives.