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An efficient and complementary copper-catalyzed alkylation of (benzo)furans/(benzo)thiophenes with cyclic ethers was reported. A broad range of C2 heteroaryl-substituted cyclic ethers were obtained in moderate to good yields. The results of control experiments indicated that this transformation might proceed via a radical process.

An efficient one-pot method involving visible-light-induced cyclization and Pd-catalyzed Suzuki cross-coupling processes to construct 3,4-diaryl coumarins is developed. Under the light on-off optimized conditions, a series of alkynoates and aryl boronic acids were well suitable for this catalytic system, and were successfully transformed into the corresponding products in moderate to high yields. Meanwhile, this synthetic system has good applicability for other Pd-catalyzed coupling reactions, such as Heck and Sonogashira reactions. 3,4,7-Triphenyl coumarin could be produced not only via the Suzuki reaction of 3-bromo-4,7-diphenyl with PhB(OH)2, but also via the Pd-catalyzed C–H activation. Based on the spectral studies, we found that some of the 3,4-diaryl coumarins may have AIE activities. This work provides a straight forward way to create valuable multi-substituted coumarins with potential AIE properties.

Three π-conjugated small molecules DPBT, DEPBT and DEPBPy, based on bithiazole or bipyridine were designed and synthesized. In DEPBT and DEPBPy, the central core and terminal phenyl groups are connected by C C double bonds, whereas in DPBT, they are combined through C–C single bonds. The effects of the molecular structural changes on their crystal structures, optoelectronic properties and thin film morphologies were comparatively studied. In addition, their resistive memory performance was primarily investigated for the first time. Both DEPBT- and DEPBPy-based devices exhibit typical binary memory behavior, while DPBT-based device presents no memory property. The experimental results confirm that the introduction of C C bridged bonds into molecules could enhance the molecular interaction, which plays an important role in the molecular arrangement on the thin film, and has a significant contribution to charge transport in memory devices. This work demonstrates that aryl vinyl terminated bithiazoles and bipyridines both are good promising candidates for organic memory storage.

Cu-catalyzed CDC reactions of coumarins with cyclic ethers and cycloalkanes were achieved to afford a variety of C-3 functionalized coumarins bearing the C(sp 2 )–C(sp 3 ) bond in moderate to excellent yields. The conversion was proposed to proceed via a radical process.

An efficient and practical bis(alkoxo)palladium complex Cat.I catalyzed C–H arylation of heterocycles with heteroaryl chlorides has been developed. With 1 mol % of Cat.I, the direct arylation of a series of heterocycles with various heteroaryl chlorides could proceed smoothly affording desired products in moderate to excellent yields. The catalytic system allows one-pot synthesis of 2,5-diheteroaryled thiophenes via twofold direct C–H arylation.

An efficient catalytic system for the palladium-catalyzed oxidative Heck reaction between arylboronic acids and various alkenes has been developed. Using the bis(aminoalkoxy)palladium complex of N,N-dimethylethanolamine as a catalyst, a series of substituted alkenes were obtained in moderate to excellent yields under mild reaction conditions. This protocol could be tolerated to arylboronic acids containing electron-donating or withdrawing groups and a wide range of olefins, such as acrylate, allyl esters, allyl ethers and alkenylphosphonate. A plausible reaction mechanism of the oxidative Heck reaction was proposed.

A novel palladium complex based on N,O-ligand was synthesized, which shows a high catalytic activity in the Suzuki cross-coupling reaction without using any phosphine ligand. More importantly, no significant loss of the catalytic activity was observed after six recycles. We suggest that this catalyst has commercial and industrial potential in the future.

A series of conjugated enynes were successfully synthesized by the palladacycle-catalyzed modified Sonogashira cross-coupling reaction of β-bromostyrene and terminal alkynes. The reaction proceeds smoothly in DMSO at 40 °C to give the corresponding products in moderate to excellent yields. This catalytic system is tolerant to a broad range of functional groups on the substrates. Moreover, the products were furnished as specific E isomers. We also found that the product of the reaction between (E)-β-bromostyrene and 2-methyl-3-butyn-2-ol is diarylated enyne in the presence of excess Cs2CO3.