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We designed a new class of N-type ligands bearing an imidazo[1,5-a]pyridine moiety and synthesized seven imidazo[1,5-a]pyridine derivatives. The palladium-catalyzed Mizoroki–Heck reaction of aryl bromides and chlorides with alkenes using our imidazo[1,5-a]pyridine-PdCl2 system afforded the desired products in good-to-high yields with the low palladium loadings and short reaction times.

We have demonstrated the Mizoroki–Heck reaction of aryl iodides with aryl allyl ethers using 1.5 mol% of imidazo[1, 5-a]pyridine–Pd catalytic system. Aryl cinnamyl ethers were obtained in moderate-to-high yield under mild reaction conditions.

An asymmetric photoreaction by using chirality provided by dynamic chiral salt formation was demonstrated. Crystallization of racemic 2-quinolone-3-carboxamide and 2-quinolone-4-carboxamide with enantiopure L-dibenzoyltartaric acid led to deracemization and gave high diastereomeric excess values of the crystalline salts in almost quantitative yield. The axial chirality was retained for a long period of time after the salts were dissolved in cooled solvent. The frozen chirality derived from the chiral salts was effectively transferred to the products by using a typical [2+2] photocycloaddition reaction with alkenes.

This article is a full account of the work exploring the potential utility of catalytic enantioselective amide allylation of various isatins using indium-based chiral catalysts. A survey of various isatin substrates and NH-containing stannylated reagents revealed that the reaction has a remarkably wide scope to result in extremely high yields and enantioselectivities (up to >99 %, 99 % ee) of variously substituted homoallylic alcohols. Several mechanistic investigations demonstrated that the substrate-reagent hydrogen-bond interaction plays a critical role in the formation of the key transition states to result in enhanced catalytic reaction. The success of this approach allowed convenient access to chiral 2-oxindoles spiro-fused to the α-methylene-γ-butyrolactone functionality and their halogenated derivatives in almost enantiopure forms, thus highlighting the general utility of this synthetic method to deliver a large variety of antineoplastic drug candidates and pharmaceutically meaningful compounds.

We report a new catalyst system, a morpholine–Pd(OAc)2 complex, for Suzuki–Miyaura coupling of aryl tosylates or mesylates with arylboronic acids to give biaryl compounds. The morpholine–Pd(OAc)2 catalyst system is proposed to be a precursor of the catalytically active species in the coupling reaction. Aryl chlorides and aryl triflates can also be used in this coupling reaction. Altogether, 22 biaryl compounds were obtained using this catalyst system.

The allylic alkylation of malonates with allylic esters is performed in high yields and with very high enantiomeric excess.

A new class of C2 chiral materials was easily prepared by the photodimerization reaction of (R)-N-phenethyl-2-chromonecarboxamide followed by recrystallization. Reduction of the photodimer gave the corresponding alcohol stereoselectively. Both C2 chiral materials worked effectively as ligands for enantioselective ethylation of arylaldehydes using diethylzinc.

The novel polysubstituted 1,1′-phenylene-bipyrrole compounds were synthesized by the double [3+2] cycloaddition-extrusion reactions of N,N′-phenylene-bimunchnones and dimethyl acetylenedicarboxylate in dry toluene at 80 °C for 24 h. Bimunchnones were prepared successfully by cyclodehydration reactions of N,N′-biacyl-N,N′-(1,4-phenylene)-bis(2-arylglycine) with N,N′-diisopropylcarbodiimide in dry toluene at 0–5 °C for 1.5 h. The structures of the products were characterized on the basis of spectral data.

Irradiation of chromone-carboxamides bearing a chiral auxiliary, e.g. (I), results in diastereoselective formation of a C2-chiral anti-HH dimer scaffold.

This article is a full account of the work exploring the potential utility of catalytic enantioselective amide allylation of various isatins using indium-based chiral catalysts. A survey of various isatin substrates and NH-containing stannylated reagents revealed that the reaction has a remarkably wide scope to result in extremely high yields and enantioselectivities (up to >99 %, 99 % ee) of variously substituted homoallylic alcohols. Several mechanistic investigations demonstrated that the substrate-reagent hydrogen-bond interaction plays a critical role in the formation of the key transition states to result in enhanced catalytic reaction. The success of this approach allowed convenient access to chiral 2-oxindoles spiro-fused to the α-methylene-γ-butyrolactone functionality and their halogenated derivatives in almost enantiopure forms, thus highlighting the general utility of this synthetic method to deliver a large variety of antineoplastic drug candidates and pharmaceutically meaningful compounds.

Organocatalytic tandem reactions of L-phenylalanine-derived tetramic acid with aldehydes allow a one-pot and high-yielding access to a diverse range of novel chiral diols in enantiomerically pure forms. In addition, a new entry of the diols, featuring their unique structures associated with C2- and pseudo C2-symmetric chiral motifs, is reported.

The previously reported carbonyl allylation of isatin derivatives with β-amido-functionalized allylstannanes is extended towards the challenging utilization of α-ketoesters as acyclic 1,2-dicarbonyl substrates.

A remarkably effective method allowing an extremely high enantioselective synthesis of the spiro-fused 2-oxindole/α-methylene-γ-butyrolactones is described. The key strategy lies in the use of indium-catalyzed asymmetric amide allylation of N-methyl isatin with functionalized allylstannanes, which can lead to the antineoplastic spirocyclic lactones in almost enantiopure forms.

Chiral crystals of quinolonecarboxamide (I) are obtained by a spontaneous crystallization and used for the preparation of cyclobutane (II) by an intramolecular photocycloaddition in the solid state.