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The intramolecular oxa-Pictet—Spengler cyclization of optically active dioxolane (I) yields cis-pyran as the major product.

The radical scavenging activities of most of the title pyridobenzoxazines (II) (13 examples) are close to or even better than commercial standards ascorbic acid and BHT.

A rapid and selective method for the title reaction is applied to a wide range of substrates.

A Pd(II)-catalyzed photochemical Heck-reaction of aryl iodides with acrylates, acryl amides, and styrene is presented giving cis-trans-mixtures of the Heck-coupling products.

The synthesis of title arylquinolinones (IV) and the corresponding coumarin derivatives (XI) is achieved by consecutive Heck reaction of o-iodoanilines (I) and o-iodophenol (X), resp., with acrylic acid (II) and aryl iodides (III) in the presence of Pd—NiFe2O4 as catalyst.

The newly synthesized dibenzothiazepines (III) are evaluated for their activity against both Gram-positive and Gram-negative bacteria.

Key step in the synthesis of title compounds (III) is the asymmetric α-aminoxylation of aldehydes (I).

The palladium supported on nickel ferrite found to be highly active catalyst for the Heck olefination of aryl iodides and activated aryl bromides providing an excellent yield in an aerobic condition, in shorter reaction time.

Phosphine-free palladium–salen complexes, N , N ′-bis(salicylidene)-ethylenediamino-palladium and N , N ′-bis(salicylidene)-1,2-phenylenediamino palladium, are found to be highly active catalysts for the Heck olefination of aryl iodides and Suzuki reaction of aryl iodides and bromides giving excellent yields (70–90%) of products under aerobic conditions, in short reaction times (10–60 min).

Regioselective nuclear bromination of aromatic compounds is investigated with N-bromosuccinimide as the brominating agent under UV irradiation to afford the corresponding brominated compounds. The reaction proceeds at ambient temperature (30 ± 2 °C) without any catalyst. In most of the reactions, regioselectively mono-brominated products are obtained in good to high yields. The conversion and selectivity for bromination depend on the nature of the substituent on the aromatic ring.

Aromatic and aliphatic carbonyl compounds undergo facile bromination with N-bromosuccinimide under UV–vis irradiation to give the corresponding α-brominated ketones in good yields, at low temperatures (30 °C), without any catalyst, catalyst support or radical initiator and within a short time.