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A new copper-catalyzed oxidative difunctionalization of enol ethers with α-amino carbonyl compounds and hydroperoxides is developed. This method is experimentally simple while allowing for regioselective access to 2-amino-3,4-dioxy carbonyl compounds in good yields, and represents the first example of alkene oxyalkylation through C(sp(3))-H functionalization.

2,3-Epoxy ketones [(III) and (V)] are synthesized through an oxidative radical pathway with a broad substrate scope and excellent selectivity control.

A novel metal-free oxidative 1,2-alkylarylation of unactivated alkenes with the α-C(sp(3))-H bonds of acetonitriles for the synthesis of 5-oxo-pentanenitriles is presented. In the presence of TBPB (tert-butyl peroxybenzoate), a variety of α-aryl allylic alcohols underwent the 1,2-alkylarylation reaction with acetonitriles, giving 5-oxo-pentanenitriles in good to excellent yields. This method proceeds via the C(sp(3))-H oxidative coupling with the C-C double bond and 1,2-aryl-migration, and represents a new access to acyclic molecules through metal-free oxidative alkene 1,2-alkylarylation.

A series of calix[10]crowns were synthesized for the first time. By reacting p-tert-butylcalix[10]arene with ethylene glycol ditosylate or polyethylene glycol ditosylates in a system of K2CO3/toluene or Cs2CO3/acetone, a series of calix[10]crowns such as 1,2-calix[10]crown-4, 1,3-calix[10]crown-2, 1,2-calix[10]crown-3, 1,3-calix[10]crown-3, 1,4-calix[10]crown-4 and 1,6-calix[10]crown-4 were obtained.

Water-soluble CdSe/ZnS quantum dots (QDs) were prepared via a simple sonochemical procedure using β-cyclodextrin (CD) as surface coating agent. The QDs displayed a sensitive emission enhancement for anthracene over other related polycyclic aromatic hydrocarbons, and the detection limit was around 1.6 × 10 −8 mol/L.

A new oxidative coupling of unactivated terminal alkenes with amides using peroxides is described, in which mono- and difunctionalization of alkenes are selectively achieved. In this reaction with amides, the chemoselectivity toward the functionalization of the C(sp(3))-H bonds adjacent to the nitrogen atom or the functionalization of the carbonyl C(sp(2))-H bonds across alkenes relies on the reaction conditions.

Calixarene-modified chitosans (CTS–CA-I and CTS–CA-II) were first synthesized by the reaction of chitosan (CTS-NH2) with 1,3-bis-chloroethoxyethoxy-2,4-dihydroxy-p-tert-butylcalix[4]arene (CA-I) or its benzoyl derivative (CA-II). Their structures were characterized by infrared and X-ray diffraction spectroscopy and scanning electron microscopy (SEM). The adsorption of Ni2+, Cd2+, Cu2+, Pd2+, Ag+, and Hg2+ by CTS–CA-I and CTS–CA-II was studied and the thermodynamic parameter of two calixarene-modified chitosans toward Hg2+ was deduced. The adsorption properties of CTS–CA-I and CTS–CA-II were greatly varied compared with that CTS-NH2, especially with the adsorption capacity toward Ag+ and Hg2+, because of the presence of the calixarene moiety. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1139–1144, 2003

p-tert- Butylcalix[4]diazacrown-4 telomer, which contains hard and soft ion binding sites, was synthesized. It exhibited high selectivity toward cesium ions. The binding sites may complex alkali metal ions selectively.

Since manipulating electromagnetic waves with electromagnetic active materials for environmental and electric engineering is a significant task, here a novel prototype is reported by introducing reduced graphene oxide (RGO) interfaces in carbon fiber (CF) networks for a hierarchical carbon fiber/reduced graphene oxide/nickel (CF-RGO-Ni) composite textile. Upon charaterizations of the microscopic morphologies, electrical and magnetic properties, the presence of three-dimensional RGO interfaces and bifunctional nickel nanoparticles substantially influences the related physical properties in the resulting hierarchical composite textiles. Eletromagnetic interference (EMI) shielding performance suggests that the hierarchical composite textiles hold a strong shielding effectiveness greater than 61 dB, showing greater advantages than conventional polymeric and foamy shielding composites. As a polymer-free lightweight structure, flexible CF-RGO-Ni composites of all electromagnetic active components offer unique understanding of the multi-scale and multiple mechanisms in electromagnetic energy consumption. Such a novel prototype of shielding structures along with convenient technology highlight a strategy to achieve high-performance EMI shielding, coupled with a universal approach for preparing advanced lightweight composites with graphene interfaces.