Decarbonylative/decarboxylative [4 + 2] annulation of phthalic anhydrides and cyclic iodoniums towards triphenylenes

Palladium-Catalyzed Annulation Reaction of Bay-Diiodinated Arenes with o-Chloroaromatic Carboxylic Acids to Access Polycyclic Aromatic Compounds

A palladium-catalyzed annulation reaction of bay-diiodinated arenes with o-chloroaromatic carboxylic acids was established. This approach enables the synthesis of a variety of polycyclic aromatic compounds, especially polyalkoxy-substituted polycyclic aromatic compounds, frequently found in discotic liquid-crystalline materials. The investigations indicate that the product 2,3,8,9,12,13-hexakis(hexyloxy)-5-azadibenzo[fg,op]tetracene demonstrates favorable room-temperature liquid-crystalline properties.

Palladium-Catalyzed Double Decarboxylative [3 + 2] Annulation of Naphthalic Anhydrides with Internal Alkynes

A palladium-catalyzed [3 + 2] annulation of naphthalic anhydrides with internal alkynes has been developed. The present protocol offers an efficient and convenient route to access a series of 1,2-disubstituted acenaphthylenes with excellent functional group compatibility. The reaction is proposed to proceed through a double decarboxylation sequence. The reported synthetic protocols can be extended to napthalene- and perylenedicarboximide-containing substrates. The molecular structures, photophysical properties, and frontier molecular orbitals of the obtained adducts were investigated by X-ray crystallography, UV-vis and fluorescence spectroscopy, and DFT calculations.

Phthalic anhydride (PA): a valuable substrate in organic transformations

This review has been centralized on applications of phthalic anhydride (PA) as a valuable and significant heterocyclic substrate in two- and multicomponent organic reactions. The article has been subdivided into the following parts: (i) PA introduction by focusing on its characterization, synthesizing procedure, and multiple-aspect applications. In addition, the previous review articles based on PA have also been indicated; (ii) the applications of PA as a substrate have been subdivided into parts with a glance on the reaction components numbers; (iii) the applications of PA in esterification reactions; and (iv) some examples of PA in multistep synthesis. The review covers the corresponding literature up to the end of 2022. According to the abovementioned classifications, PA is a potent substrate to design a wide range of heterocyclic compounds that possess various kinds of properties and applications in chemistry, industry, and pharmaceuticals.