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A two-step reaction to convert terminal alkynes into triborylalkenes is reported. In the first step, the terminal alkyne and pinacolborane (HBpin) are converted into an alkynylboronate, which is catalyzed by an iridium complex supported by a SiNN pincer ligand. In the second step, treatment of the reaction mixture with CO generates a new catalyst which mediates dehydrogenative diboration of alkynylboronate with pinacolborane. The mechanism of the diboration remains unclear but it does not proceed via intermediacy of hydroboration products or via B2 pin2.

The two-step approach for the synthesis of triborylalkenes starts with the conversion of terminal alkynes and pinacolborane (HBpin) into alkynylboronate catalyzed by a SiNN pincer ligand supported iridium complex, followed by treatment of the reaction mixture with CO for the generation of a new catalyst.

The first Ni-promoted prototype reaction based on the tandem C–H activation of heteroarenes with alkene isomerization is demonstrated, leading to the branched hydroheteroarylation products. Simultaneously, the reaction selectivity can be chemically switched to linear adducts through Ni–Al tandem catalysis.

An amino-linked nitrogen heterocyclic carbene mediates the carbon—carbon coupling reaction through direct C—H functionalization of benzene (II) and pyridine (IV) with aryl iodides (I) in the absence of a metal catalyst.

We have disclosed a new mode of a chemically regioselective switch for C–H bond functionalization of benzimidazole derivatives via a cooperative effect invoked by Ni–Al bimetallic catalysis to create a steric requirement for obtaining the linear product of styrene insertion. Yet, excluding the AlMe3 cocatalyst switches the reaction toward branch selectivity.

A convenient method for the synthesis of highly substituted isoquinolines and isoquinolinium salts by the nickel-catalyzed cyclization of ortho-haloketoximes and -ketimines, respectively, with alkynes is described. The reaction of ortho-haloketoximes and various alkynes in the presence of [Ni(PPh(3))(2)Br(2)] and zinc powder in a mixture of acetonitrile and tetrahydrofuran at 80 °C for 15 hours gave 1,3,4-trisubstituted isoquinoline products in moderate to excellent yields and high regioselectivity. The corresponding isoquinoline N-oxide was found to be the intermediate in the cyclization reaction pathway. In contrast, the reaction of ortho-haloketimines and alkynes under similar catalytic conditions in tetrahydrofuran at 70 °C for two hours gave 1,2,3,4-tetrasubstituted isoquinolinium salts in good to excellent yields.