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A copper-catalyzed S-methylation of sulfonyl hydrazides with TBHP was efficiently developed, providing a variety of methyl sulfones with good to excellent yields. The reaction can be carried out in water smoothly without any ligand or additive under mild conditions and this catalyst-in-water can be recycled several times.

A novel copper-catalyzed dual oxidative benzylic C H aminations of methylarenes with 2-aminobenzoketones in the presence of ammonium acetate was developed. This reaction represents a new avenue for 2-arylquinazolines with good yields. A key intermediate was detected and the kinetics isotope effect (KIE) indicated that C H bond cleavage was the rate-determining step.

Anthranilic acid amides are cyclized to the corresponding dihydro-quinazolinones in good yields with dicumyl peroxide as radical methyl donor.

A copper-catalyzed radical methylation/sp(3) C-H amination/oxidation reaction for the facile synthesis of quinazolinone was developed. In this cascade reaction, dicumyl peroxide acts not only as a useful oxidant but also as an efficient methyl source. Notably, a methyl radical, generated from peroxide, was confirmed by electron paramagnetic resonance for the first time.

Herein, we report a new pyridine-biquinoline-derivative fluorophore L for effectively sensing pyrophosphate (PPi) and monohydrogen sulfide (HS(-)) in aqueous buffer and in living cells. L could selectively coordinate with metal ions (M(n+)) in Groups IB and IIB to form L-M(n+) complexes with 1:1 stoichiometry, resulting in fluorescence quenching via photoinduced electron transfer (PET) mechanism. L-Zn(2+) complex was applied to competitively coordinate with PPi to form a new "ate"-type complex, turning on the fluorescence by a 21-fold-increase. The limit of detection (LOD) of this assay for PPi detection in aqueous buffer is 0.85 μM. L-Cu(2+) complex was applied for highly selective detection of HS(-) with an excellent sensitivity by 25-fold decomplexation-induced fluorescence increase. LOD of L-Cu(2+) complex for HS(-) detection in aqueous buffer is 2.24 μM. With the in vitro data obtained, we successfully applied these two complexes for sequential imaging Zn(2+) and PPi, Cu(2+) and HS(-) in living cells, respectively. Since PPi and HS(-) occur in vascular calcification in positive correlation, our multifunctional probe L might help doctors to more precisely diagnose this disease in vivo in the future. For example, we could use radioactive tracer L-(64)Cu for qualitative and quantitative positron emission tomography/computed tomography (PET/CT) imaging of HS(-) in vivo.

Tetraphenyladamantane-based microporous polyimide was synthesized. It can uptake 14.6 wt% CO2 at 273 K and 1 bar, 99.2 wt% benzene and 59.7 wt% cyclohexane at 298 K and 0.9 bar, exhibiting potential applications in gas storage and recovery of organic pollutants.

Four new polyimide networks were prepared via a one-step polycondensation method by using tris(4-aminophenyl)amine and 1,3,5-tris(4-aminophenyl)benzene to react with pyromellitic dianhydride (PMDA) and naphthalene-1,4,5,8- tetracarboxylic dianhydride (NTDA), respectively. It was found that the topological structures and pore morphologies of the networks were tightly related to the geometrical shape of the net nodes, the molecular volume of the connecting struts, the reactivity of the monomers as well as the polymerization conditions. The results revealed that the reactions between triangular triamines and rod-like PMDA tended to form six-membered ring units, which were then extended to yield polyimide crosslinking networks, reflected by the complete disappearance of the endgroup signals in the FTIR and 13C CP MAS spectra, the significantly high thermal stability, large accessible surface area (818 cm2 g−1) and narrow pore size distribution centered at 4–8 A. On the contrary, the low reactivity and steric bulky naphthyl group of the NTDA monomer led to the generation of branched or hyperbranched oligomers, which were further mutually crosslinked at a high temperature to produce the polyimde networks. In this way, a small amount of unreacted groups unavoidably remained, and the polymers exhibited a heterogeneous topological architecture, a broad pore size distribution and a low surface area of only 232 cm2 g−1. The influences of synthetic control and monomer structures on the pore morphologies and properties are investigated.