A novel [1, 2, 4]triazolo[5,1-b]quinazoline derivative as a fluorescent probe for highly selective detection of Fe3+ ions.

A novel [1, 2, 4]triazolo[5,1-b]quinazoline fluorescent probe (VIi) for Fe3+ was developed, featuring with rapid response (< 5 s) and specific selectivity to Fe3+, low detection limit (1.3 × 10-5 M), as well as the ability to resist interference of chelating agent (e.g. EDTA). VIi-based fluorescent test paper can quickly recognize Fe3+ under irradiation at the wavelength of 365 nm. The fluorescence probe VIi has potential application prospects for the detection of Fe3+ in real circumstance.

Brønsted Acid-Catalyzed Minisci-Type Cross-Dehydrogenative Coupling of N-Heteroaromatics and Cyclic Ethers.

Brønsted acid-catalyzed direct C(sp2)-H alkylation of N-heteroaromatics with cyclic ethers via a cross-dehydrogenative coupling reaction in the presence of benzoyl peroxide was developed. This methodology successfully provided an easy access to a variety of alkyl-substituted quinoxaline, benzoimidazole, pyrazine, pyrimidine, quinoline, isoquinoline, and pyridine derivatives in up to 94% yield under metal-free conditions.

Chemistry of heterocyclic ketene aminals: construction of imidazo(pyrido)[1,2-a]pyridines and imidazo(pyrido)[3,2,1-ij][1,8]naphthyridines via DABCO-catalyzed tandem annulations.

2-(2-Chloroaroyl)methyleneimidazolidines with four reactive sites show fascinating structural features and could be used as a new strategy for the synthesis of novel heterocycles. This paper presents our new findings in the reaction of 2-(2-chloroaroyl)methyleneimidazolidines with allenic esters affording functionalized imidazo(pyrido)[1,2-a]pyridines via DABCO-catalyzed tandem annulations. Of particular significance is the incorporation of an o-halo group into the aryl ring of 2-benzoylmethylene-imidazolidines to set up a convenient and general way for constructing unusual imidazo(pyrido)[3,2,1-ij][1,8]naphthyridines.