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Sterically hindered substrates can be employed in an enantioselective palladium-catalyzed α-arylation with the chiral monophosphorus ligand BI-DIME. This process enabled an efficient synthesis of the antidepressant (S)-nafenodone, a four-step enantioselective synthesis of the Sceletium alkaloid (+)-sceletium A-4, a concise five-step enantioselective synthesis of (-)-corynoline, as well as a three-step preparation of (-)-DeN-corynoline.

A palladium-catalyzed aerobic and ligand-free Suzuki reaction in aqueous ethanol has been developed for the synthesis of N-heteroaryl substituted 9-arylcarbazolyl derivatives. A number of N-heteroaryl halides, namely 2-halogenated pyridines, 2-bromoquinoline, 5-bromopyrimidine and 2-chloropyrazine, were coupled with 4-(9H-carbazol-9-yl)phenylboronic acid (CPBA) or 9-phenyl-9H-carbazol-3-ylboronic acid (PCBA) efficiently to afford good to excellent yields in a short reaction time. Moreover, the catalytic system of Pd(OAc)(2)-EtOH/H(2)O-K(2)CO(3) was successfully extended to the cross-couplings of N-heteroaryl halides with various arylboronic acids. The results demonstrated that the cross-coupling reaction in the present protocol was promoted by oxygen.

This paper reports an efficient synthesis of triphenylamine (TPA) derivatives via a palladium-catalyzed Suzuki reaction of (hetero)aryl halides with 4-(diphenylamino)phenylboronic acid (DPBA) in aqueous ethanol under aerobic and ligand-free conditions. Heteroaryl halides, namely pyridyl bromides, quinolyl bromides, pyrimidinyl bromides, 2-chloropyrazine and sulfur-containing heteroaryl bromides, could react smoothly with DPBA, affording good to excellent yields under mild conditions. In addition, aryl bromides were also successfully employed in the cross-couplings with DPBA and furnished the products in high yields at room temperature. The cross-coupling of 4-bromobenzonitrile with DPBA gave the desired product in a quantitative yield within 2 min, resulting in a TOF up to 5820 h 21 .

An aerobic, ligand‐free Suzuki reaction catalyzed by Pd/C in aqueous media has been developed. This method is a very simple, efficient and mild protocol for the cross‐coupling of aryl bromides with arylboronic acids, and the reactions proceeded smoothly in excellent yields within short reaction times. Control experiments demonstrated that the Pd/C‐catalyzed Suzuki reaction was much quicker when performed in air or oxygen than in nitrogen. Furthermore, this protocol could be used for the synthesis of fluorinated liquid‐crystalline compounds. The Pd/C catalyst could be recovered and recycled efficiently at least ten times without significant loss of catalytic activity.

H-β Zeolites, doped with various metal salts, were investigated as heterogeneous catalysts for continuous-flow Friedel-Crafts acylation reactions. It was found that Zr-β zeolites possessed excellent catalyst activity and stability, which enabled its use as a catalyst, up to 5 days, for Friedel-Crafts reactions between various activated arenes and acid anhydrides. Challenging substrates, such as toluene and mxylene, were also successfully applied for the continuousflow process.[a] Dr.

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