•A facile and economical catalytic synthesis of 3-substituted isocoumarins was achieved.•2-Chloro-benzoic acids/amides were utilized as starting materials with 1,3-diketones.•Copper nanoparticle catalyst shows highly catalytic activity for the 2-chloro-substituted substrates.Copper nanoparticles were utilized as a highly efficient catalyst for a facile and economical synthesis of 3-substituted isocoumarins with 2-chlorobenzoic acids and 1,3-diketones as starting materials. The copper nanoparticles catalyst showed highly catalytic activity for the 2-chloro-substituted substrates to afford 3-substituted isocoumarins in good to excellent yields. Furthermore, good catalytic activity was also observed when 2-chlorobenzoic amides were utilized as substrates instead of the benzoic acids.Download high-res image (78KB)Download full-size image

A facile, highly efficient, and practical one-pot synthetic strategy for benzoxazoles was developed by using copper nanoparticles as a catalyst with o-bromoanilines and acyl chlorides as starting materials. With the promotion of 1,10-phenanthroline ligand, the copper nanoparticles catalyst showed highly catalytic activity under mild conditions. This methodology is tolerant of a wide variety of functional groups and gives good to excellent yields in most examples. Furthermore, the solid catalyst could be recovered and reused conveniently several times with satisfactory yields.

Supported copper nanoparticles are utilized for the first time as a highly efficient and reusable catalyst in the coupling of acyl chlorides and terminal alkynes to prepare various ynones. The reaction is carried out under palladium-, ligand-, and solvent-free conditions. The catalyst can be simply recovered and reused several times without significant loss in catalytic activity.

A highly efficient annulation of 2-(1-hydroxy-3-arylprop-2-ynyl)phenols leading to the key intermediates to synthesize aurones was catalyzed by silver nanoparticles/carbon black-supported silver nanoparticles. In the presence of phosphine ligand, both the catalysts show excellent catalytic activities in the reaction and give the products with good yields as well as excellent regio- and stereo-selectivities in a water-toluene mixed solvent. Furthermore, the catalysts can be recovered and recycled effectively several times.

A highly efficient alkynylation-cyclization of terminal alkynes with salicylaldehydes leading to substituted 2,3-dihydrobenzofuran-3-ol derivatives was developed by using Cy3P−silver complex as catalyst in water. Counter anions in the silver complex proved to be the key factor to Z/E stereoselectivity control. Aurones can also be obtained effectively from the cascade reaction followed by oxidation without further purification.