An efficient catalytic system for the ligand-free Suzuki–Miyaura reaction in water at room temperature is disclosed, promoted by Stilbazo (stilbene-4,4′-bis[(1-azo)-3,4-dihydroxybenzene]-2,2′-disulfonic acid diammonium salt). The desired carbon–carbon bond formation proceeded well under mild conditions with high efficiency and good functional group tolerance.

Nitrogen heterocycles are of great medicinal importance, and the construction of nitrogen heterocyclic scaffolds has been one of the focuses in synthetic organic chemistry. Recently, the strategy of transition metal-catalyzed sp³ C–H activation and intramolecular C–N coupling to construct nitrogen heterocyclic scaffolds has been well developed. Palladium, copper, silver, nickel, cobalt, ruthenium and rhodium catalysis were successfully used for the construction of nitrogen heterocyclic scaffolds, aziridines, azetidines, pyrrolidines, pyrrolidine-2,5-diones, indolines, isoindolines, isoindolinones, tetrahydropyridines, oxazolidinones, oxazinanones, β-lactams, γ-lactams etc., which have been synthesized by the sp³ C–H activation strategy. Here, we summarize the progress of transition metal-catalyzed sp³ C–H activation/intramolecular C–N bond formation, and introduce both the reaction development and mechanisms in numerous synthetically useful intramolecular sp³ C–H catalytic aminations/amidations.

The quinazolinone skeleton is a common structure found in natural alkaloids and synthetic drugs. In recent years, some quinazolinone derivatives have been found to exhibit good luminescence properties. Benefitting from excellent biocompatibility, low toxicity, and high efficiency, quinazolinones have become promising candidates for use as fluorescent probes, biological imaging reagents and luminescent materials. This review focuses on recent advances relating to the luminescence properties of quinazolinones and their applications in fluorescent probes, biological imaging. Fluorescent probes based on the 2-(2′-hydroxyphenyl)-4(3H)-quinazolinone (HPQ) structure are summarized. Newly developed quinazolinone molecules for environmentally sensitive probes and two photon fluorescence bioimaging are discussed. A brief outlook relating to the future of quinazolinone-based probes and luminescent materials is also included.