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Highly substituted iodobenzenes were efficiently and regioselectively synthesized from readily available 1,6-diynes through two-step process consisting of silver-catalyzed Csp-H iodination and subsequent ruthenium-catalyzed cycloaddition of resultant iododiynes. One of the obtained p-diiodobenzenes was utilized as a halide component for cross-coupling reactions such as Mizoroki-Heck reaction, Sonogashira reaction, and Suzuki-Miyaura coupling.

Cp*RuCl-catalyzed cycloadditions of alpha, omega-diynes with electron-deficient carbon-heteroatom multiple bonds results in various heterocyclic compounds with significant chemo- and regioselectivity. The regiochemistry of these cycloadditions was successfully controlled by the steric and electronic influence of the unsymmetrical diyne substrates.

Palladium(O)-catalyzed cyclodimerization and cycloisomerizations of enyne esters is described. Uncommon six-membered ring products were predominantly formed with concomitant enyne metathesis products when enyne esters bearing a methallyl moiety were used.

The synthesis of three 4-substituted bis(oxazolinyl)pyridines and their rhodium complexes allows the study of the effect of their substituents in the catalytic asymmetric hydrosilylation of ketones. The study shows that introduction of substituents affects the critical reaction temperature at which the rhodium catalyst and silane effect smooth reduction of the ketone. Electron-withdrawing groups speed up the reaction while electron-donating groups slow it down. The substituents also enhance the enantioselectivity up to 90-94%.

Polybromoanisoles and aliphatic Grignard reagents can undergo metal-halogen exchange reaction forminghalide aromatic Grignard reagents and cyclopenta(b)benzofuran skeletons. The reaction between polybromoanisole and alkyl Grignard reagents in the presence of tetrahydrofuran exhibits the exchange of only one bromine atom that is orthoto the methoxy group. The reaction opens a new route for the study of selectiveorganic functional group conversion.

A novel four-component coupling strategy is explored to synthesize polycyclic pyrrole-2-carbohydrates. The approach comprises the relay process of the Cu-catalyzed three-component condensation giving rise to glycinate-tethered 1,6-enynes and the subsequent Ir-catalyzed cycloisomerization/Diles-Alder cycloaddition/dehydrogenative aromatization.

Highly substituted phthalides are efficiently synthesized by sequential Cp*RuCl-catalyzed cyclotrimerization of alkynylboronates, propargyl alcohols, and terminal alkynes and palladium(II) catalyzed carbonylation of the resultant arylboronates. The perfect regioselectivity of the ruthenium-catalyzed formal intermolecular cyclotrimerization is discussed on the basis of the density functional calculations of a boraruthenacycle intermediate.

A new efficient catalytic system for the highly anti-selective and enantioselective reductive aldol reaction of acrylates and aldehydes with hydrosilanes is found. It is found that Rh(Phebox) complexes act as efficient catalysts for the asymmetric conjugate reduction of alpha, beta-unsaturated esters with several hydrosilanes.

The chemo-and regioselective catalytic cyclomerization of unsymmetrical three alkyne components, by means of the temporary tethering approach with ruthenium catalysis is reported. The catalytic intermolecular cyclotrimerization of three different unsymmetrical alkynes can be accomplished with the help of ruthenium catalysis.