Facile synthesis of N-doped graphene quantum dots as a fluorescent sensor for Cr(vi) and folic acid detection.

The development of stable fluorescent sensors for toxic pollutants and drugs is meaningful to the environment and public health. In this work, nitrogen-doped graphene quantum dots (N-GQDs) were facially synthesized by a one-step hydrothermal method using soluble starch and l-arginine as carbon and nitrogen sources in pure water at 190 °C for 4 h. The as-synthesized N-GQDs were well characterized and displayed blue fluorescence emission at 445 nm with excellent pH stability, salt tolerance, thermostability, photobleaching resistance and reproducibility.

Photoexcited sulfenylation of C(sp)-H bonds in amides using thiosulfonates.

A photoexcited sulfenylation of C(sp)-H bonds in amides is developed for the synthesis of sulfenyl amides using thiosulfonates as a sulfur source. In the presence of easily available and inexpensive Na-eosin Y, TBHP and KCO, various sulfenyl amides can be obtained under the irradiation of blue light at room temperature.

An amino-substituted 2-(2'-hydroxyphenyl)benzimidazole for the fluorescent detection of phosgene based on an ESIPT mechanism.

In this work, an ESIPT-based fluorescence probe, 5'-amino-2-(2'-hydroxyphenyl)benzimidazole (P1), was synthesized and explored for the ratiometric detection of phosgene. Compared to 2-(2'-hydroxyphenyl)benzimidazole (HBI), P1 exhibits high sensitivity (LoD = 5.3 nM) and selectivity toward phosgene with the introduction of the amine group.

Visible-light-promoted synthesis of secondary and tertiary thiocarbamates from thiosulfonates and -substituted formamides.

A general visible-light-promoted metal-free synthesis of secondary and tertiary thiocarbamates starting from thiosulfonates and -substituted formamides is developed. By employing rhodamine B as a photocatalyst and -butyl hydroperoxide (TBHP) as an oxidant, a wide scope of thiocarbamates can be obtained through direct thiolation of acyl C-H bonds under irradiation of blue light at room temperature for 12 h.

H-phosphonate-mediated sulfonylation of heteroaromatic N-oxides: a mild and metal-free one-pot synthesis of 2-sulfonyl quinolines/pyridines.

A smart H-phosphonate-mediated synthetic strategy for the sulfonylation of heteroaromatic N-oxides has been developed, by which a large variety of 2-sulfonyl quinolines/pyridines were synthesized starting from easily available sulfonyl chlorides, diisopropyl H-phosphonate and pyridine/quinoline N-oxides in one pot under metal-free conditions at room temperature.

A one-pot strategy to synthesize β-ketophosphonates: silver/copper catalyzed direct oxyphosphorylation of alkynes with H-phosphonates and oxygen in the air.

A highly efficient one-pot strategy has been developed for the synthesis of β-ketophosphonates directly from alkynes and dialkyl H-phosphonates in the presence of widely available AgNO3/CuSO4 and K2S2O8 at room temperature under open-air conditions.

Peroxides as "switches" of dialkyl H-phosphonate: two mild and metal-free methods for preparation of 2-acylbenzothiazoles and dialkyl benzothiazol-2-ylphosphonates.

Two mild and metal-free methods for the preparation of two kinds of important benzothiazole derivatives, 2-acylbenzothiazoles and dialkyl benzothiazol-2-ylphosphonates, respectively, were developed. The dialkyl H-phosphonate (RO)2P(O)H exists in equilibrium with its tautomer dialkyl phosphite (RO)2POH. TBHP triggered α-carbon-centered phosphite radical formation, whereas DTBP triggered phosphorus-centered phosphonate radical formation.