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Rich in antioxidants with a variety of flavones and anthocyanins, passionflower/fruit has been extensively used in food, beverage, medicinal, and natural dyes industries. The individual components present in passionflower are identified by extracting them in methanol, partitioning them between ethyl acetate and aqueous layers, and recording their ESI mass spectrometric data. The steady‐state absorption and fluorescence spectra of the extract in methanol and dimethyl sulfoxide are recorded and the lifetime of the fluorescing species is reported. The pH dependence of the absorption spectrum confirms the presence of the anthocyanins. [ABSTRACT FROM AUTHOR]

This article discusses a new method for synthesizing benzo[b]carbazoles, which are compounds with various applications in medicinal chemistry and materials science. The researchers also explored the liquid crystalline properties of these compounds and successfully achieved a rare nematic phase at room temperature. By fusing a benzene ring and tethering two alkoxyphenyl units, they were able to stabilize the nematic phase. The degree of order in the liquid crystals was influenced by the length of the alkyl chains. This research highlights the significance of innovative molecular designs in creating functional materials. [Extracted from the article]

Catalysis by trivalent nucleophilic organophosphines has emerged as an essential tool in organic synthesis. Several new organic transformations promoted by phosphines substantiate and complement the existing synthetic chemistry tools. Mere design of the substrate and reagent combinations has introduced new modes of reactivity patterns, which are otherwise difficult to achieve. These design considerations have led to the rapid build-up of complex molecular entities and laid a solid foundation to synthesise bioactive natural products and pharmaceuticals. This article presents an overview of some of the conceptual advances, including our contributions to nucleophilic organophosphine chemistry. The scope, limitations, mechanistic insights, and applications of these metal-free transformations are discussed elaborately. [ABSTRACT FROM AUTHOR]

The synthesis of monosubstituted tetrahydrocarbazoles is achieved via the palladium-catalyzed formal [4+2] cycloaddition of 2-alkyl-3-indolylmethyl carbonates and monosubstituted olefins. The transformation demonstrates an unusual C(sp3)–H activation enabled by (η3-indolylmethyl)palladium complexes. The regioselectivity is found to be dependent on the nature of the substituent across the olefin component. Elaborate mechanistic studies are performed, and the synthetic utility of the products is also demonstrated. [ABSTRACT FROM AUTHOR]

We describe the first metal-free and organocatalytic strategy to access highly functionalised dibenzocycloheptanes via a phosphine-promoted annulative Morita–Baylis–Hillman (MBH) reaction. The method is manipulated to access to chiral dibenzocycloheptanes as well. This work represents a rare entry for the construction of seven-membered carbocycles via the MBH route. The realisation of several bioactive molecules possessing the dibenzocycloheptane core makes this an attractive strategy. [ABSTRACT FROM AUTHOR]

An overview of the recent literature on palladium‐catalyzed intramolecular Alder‐ene (IMAE) reaction of a variety of 1,n‐unsaturated systems is presented. The reaction which was first reported by Trost and Lautens provided an efficient alternative to the thermal or Lewis acid catalyzed cycloisomerizations involving ene‐type reaction. The IMAE cyclization of enynes and dienes has emerged as an important area and found significant applications in building up of complex molecular architectures and in the synthesis of several bioactive natural products. Since highly impactful reviews on this subject have covered the literature till 2015, this article focuses on summarizing the works subsequent to 2015. [ABSTRACT FROM AUTHOR]

Desymmetrization‐based protocols for the synthesis of highly functionalized indeno‐spirocyclopropanes and cyclopropa‐fused indanes have been established through unexpected reactions triggered by the Corey–Chaykovsky reagent. These structures were further elaborated in one step to privileged scaffolds such as fluorenones, indenones, and naphthaphenones. For instance, an acid‐catalyzed transformation of indeno‐spirocyclopropanes provided fluorenones via a homo‐Nazarov‐type cyclization, and naphthaphenones were obtained via an acid‐catalyzed cyclopropane ring‐opening/retro‐Michael sequence. [ABSTRACT FROM AUTHOR]