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We report a direct C-H aminoalkylation reaction using two light-activated H-atom transfer catalyst systems that enable the introduction of protected amines to native adamantane scaffolds with C-C bond formation. The scope of adamantane and imine reaction partners is broad and deprotection provides versatile amine and amino acid building blocks. Using readily available chiral imines, the enantioselective synthesis of the saxagliptin core and rimantadine derivatives is also described.

An N-heterocyclic carbene (NHC)-catalyzed strategy has been developed to address the issue of using toxic transitional metals in the field of C-C bond activation. The novel reaction mode enables an efficient docking between the cyanoalkyl from the cycloketone oxime derivative and the acyl group from the aldehyde, affording ketonitrile in moderate to good yields, which is one kind of useful building block for synthesizing nitrogen-containing pharmacophores.

A new general de novo synthesis of pharmaceutically important α-aryl β-perfluoroalkyl ketones has been disclosed. Compared with trifluoromethylation-initiated radical 1,2-aryl migration of α,α-diaryl allylic alcohols, this protocol employs a new strategy of biomimetic carbene catalysis to assemble alkene, aldehyde and perfluoroalkyl reagents, providing access to products with excellent flexibility of the aryl unit and perfluoroalkyl group. This method also demonstrates excellent functional group compatibility, including some Grignard reagent sensitive groups.

A nickel-catalyzed 1,2-aminoarylation of oxime-ester-tethered alkenes with boronic acids was developed. A variety of pyrroline derivatives were synthesized in good yields via the successive formation of C(sp3)–N and C(sp3)–C(sp2) bonds. For cyclobutanone-derived oxime esters, the reaction provided aliphatic nitriles incorporating an aromatic group in the γ-position. A mechanism involving iminyl radical and carbon-centered radical intermediates was proposed.

A new method for the direct functionalization of diamondoids has been developed using photoredox and H-atom transfer catalysis. This C–H alkylation reaction has excellent chemoselectivity for the strong 3º C–H bonds of adamantanes in polyfunctional molecules. In substrate competition reactions, a reversal in selectivity is observed for the new H-atom transfer catalyst reported here when compared to six known photochemical systems. Derivatization of a broad scope of diamondoids and adamantane-containing drugs highlights the versatility and functional group tolerance of this C–H functionalization strategy.

A novel amine-catalyzed nucleophilic trifluoromethylthiolation between Morita–Baylis–Hillman carbonates and O-octadecyl-S-trifluorothiolcarbonate has been developed. The regioselectivity of this reaction can be controlled by choosing different solvents, affording primary allylic SCF3 products in THF and secondary allylic SCF3 products in CHCl3 as major products. The mechanistic investigation indicated that DABCO plays a dual role in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates.

A redox-economical strategy for the synthesis of trifluoromethylated enamides using copper catalysis is reported. The reaction employs the inexpensive Langlois reagent (CF3SO2Na) and takes place without the need of an external oxidant. The trifluoromethylated enamide products can easily be converted into the corresponding ketone, saturated amide or oxazole.

Hydroquinine anthraquinone-1,4-diyl diether [(DHQ)(2)AQN]-catalyzed unprecedented asymmetric domino annulation reactions of acylidenoxindoles/isatins, acylidenoxindoles and allenoates are disclosed in this communication, providing a facile access to hexahydrofuro[2,3-b]furans containing four contiguous chiral centers in good to excellent yields along with good to excellent ee values and moderate to good dr values. Based on theoretical investigations, a concerted [3+2] ring-closure process was proposed, in which steric hindrance and pi-pi stacking interaction between catalyst and substrate subtly co-control the diastereoselectivity of the reaction.

Mesoporous titanium dioxide/graphitic carbon microspheres were synthesized by a simple nanocasting route using monodisperse silicon dioxide microspheres as the template. The characterize and the morphology of the titanium dioxide/graphitic carbon microspheres have been analyzed by means of XRD, N2-sorption, SEM, TEM, TG-DTA and EDAX. Indicated by the experimental results and the theoretical analysis, the anatase titanium dioxide nanoparticles of 8-14 nm in diameter were highly dispersed in the graphitic carbon microspheres. The obtained material can be used as catalyst or battery material. Key words: titanium dioxide/graphitic carbon; Microspheres; Nanocasting route;Mesoporous

An iron-catalyzed coupling reaction of O-acyloximes and O-benzoyl amidoximes with silyl enol ethers is reported. The protocol provides access to functionalized pyrroles, 1,6-ketonitriles, pyrrolines and imidazolines via carbon-centered radicals generated from an initially formed iminyl radical. The intramolecular cyclization and ring-opening processes of the iminyl radical take place preferentially over reactions that proceed through a 1,3-hydrogen transfer, providing insights into iron-catalyzed reactions with oxime derivatives. The cheap and environmentally friendly iron catalyst, the broad substrate scope and the functional group compatibility make this protocol useful for synthesis of valuable nitrogen-containing products.

The reaction of isoquinoline and allenoate with activated ketone resulted in a novel three component reaction, affording [1,3]oxazino[2,3-a]isoquinoline derivatives in moderate yields along with moderate diastereoselectivities via 1,4-dipolar cycloaddition. It was also found that when isatins were used as substrates, the regioselectivity of cycloadducts was different from those using ethyl trifluoropyruvate as substrate.

One-pot thermal-induced [3+2] cycloaddition/silica gel-promoted fragmentation sequence between isatin ketonitrones and electron-deficient alkynes affords spiro[indoline]oxindoles in moderate to excellent yields along with good diastereoselectivities. The detailed mechanism of silica gel-promoted fragmentation has been clarified by experiment and DFT calculations.

Breviflavone B is a novel chiral phytoestrogen that mimics the biological functions of 17β-estradiol (E2), an estrogen which is naturally produced in our body. It has exhibited a much higher estrogen receptor (ER) bioactivity than E2 or other phytoestrogens. Breviflavone B specifically activates ER at a low dose without activating other steroid receptors, and inhibits estrogen-stimulated breast cancer cell proliferation at high doses, making it a potential treatment option for breast cancer patients. In this report, a new liquid chromatography aprroach has been developed to isolate Breviflavone B from Epimedium Brevicornum herbal extracts. After passing through DIAION HP20 resin, the ethanolic extract of Epimedium Brevicornum was firstly fractionalized by a Diol column, then further separated by a C18 column using preparative HPLC, and finally purified by an ODS-MCR-HPS column in HPLC under gradient mode. In each stage of separation, the ER bioactivities of the each fraction were measured by estrogen receptor-driven reporter gene bioassays to guide the chromatographic fractionations. The results showed that the new combination of Diol and C18 and ODS-MCR-HPS column chromatography provided better separation selectivity than our previously-reported C18 column chromatography for isolation of Breviflavon B from Epemidium herbs. Pure Breviflavon B was successfully isolated from the ethanolic extract of Epimedium Brevicornum herb via this new approach of chromatographic fractionations guided by the bioassays.

Biological treatment played an important role in the treatment of landfill leachate. In the current study, acid mine drainage (AMD) was used as a source of sulfate to strengthen the anaerobic treatment of landfill leachate. Effects of chemical oxygen demand (COD) and SO42- mass concentration ratio on the decomposition of organic matter, methane production and sulfate reduction were investigated and the microbial community was analyzed using the high throughout methods. Results showed that high removal efficiency of COD, methane production and heavy metal removal was achieved when the initial COD/SO42- ratio (based on mass) was set at 3.0. The relative abundance of anaerobic hydrogen-producing bacteria (Candidatus Cloacamonas) in the experimental group with the addition of AMD was significantly increased compared to the control. Abundance of hydrogenotrophic methanogens of Methanosarcina and Methanomassiliicoccus was increased. Results confirmed that AMD could be used as sulfate resource to strengthen the biological treatment of landfill leachate.

A novel intramolecular oxycyanation of methylenecyclopropanes is reported that proceeds through oxidative cleavage of the N-CN bond and subsequent palladium transfer from N to O of the amide group. A range of substituted benzo[d][1,3]oxazines with a cyano group are readily furnished by this newly developed oxycyanation reaction. Tris(4-trifluoromethylphenyl)phosphine as a ligand has been found to be crucial to effectively promote the transformation with high chemo- and regioselectivity. Moreover, the reaction outcome can be significantly affected by the electronic effect of the acyl group attached to the nitrogen atom of methylenecyclopropanes. When R(3) is a chloromethyl group, the pyrrolo[2,3-b]quinoline derivative is obtained by thermal-induced [3+2] cycloaddition of methylenecyclopropane to the methanediimine intermediate.

Treatment of pyridine and dimethyl acetylenedicarboxylate derivatives with N-substituted isatylidene derivatives resulted in three-component condensations, affording 1′,9a′-dihydrospiro[indoline-3,2-quinolizin]-2-one derivatives in high yields and with good diastereoselectivities through 1,4-dipolar cycloadditions.

A novel intramolecular oxycyanation of methylenecyclopropanes is reported that proceeds through oxidative cleavage of the N-CN bond and subsequent palladium transfer from N to O of the amide group. A range of substituted benzo[d][1,3]oxazines with a cyano group are readily furnished by this newly developed oxycyanation reaction. Tris(4-trifluoromethylphenyl)phosphine as a ligand has been found to be crucial to effectively promote the transformation with high chemo- and regioselectivity. Moreover, the reaction outcome can be significantly affected by the electronic effect of the acyl group attached to the nitrogen atom of methylenecyclopropanes. When R(3) is a chloromethyl group, the pyrrolo[2,3-b]quinoline derivative is obtained by thermal-induced [3+2] cycloaddition of methylenecyclopropane to the methanediimine intermediate.

A novel amine-catalyzed nucleophilic trifluoromethylthiolation between Morita–Baylis–Hillman carbonates and O-octadecyl-S-trifluorothiolcarbonate has been developed. The regioselectivity of this reaction can be controlled by choosing different solvents, affording primary allylic SCF3 products in THF and secondary allylic SCF3 products in CHCl3 as major products. The mechanistic investigation indicated that DABCO plays a dual role in activating the Zard's trifluoromethylthiolation reagent and the MBH carbonates.

Highly ordered nanotube arrays were fabricated via electrochemical anodization of Ti-6Al-4V (TC4) alloy foils in aqueous fluorine containing electrolytes. The formation of ordered nanotubular films was affected by the applied anodization potential and the anodization time. The optimal applied voltage and anodization time were 20V and 1h, respectively, as-prepared anodic nanotubular films were in highly ordered with the average inner diameter of about 120nm, the wall thickness of 17nm and the tube length about 300nm. The tubular nanostructures were examined by field emission scanning electron microscopy. The possible nanotube formation mechanism was also discussed.

Nanotubular films on the surface of Ti-2Al-1.5Mn (TC1) alloy were fabricated by electrochemical anodization technique in aqueous ammonium fluoride solutions at 20V for 3h. The photoelectrochemical activities of the nanotube arrays were investigated, as well as their phase, structure, composition and photoabsorption properties. The photo-absorption in the visible region and the photoelectrochemical response were improved obviously. It is attributed to the Mn ion doping of TiO2 lattices. Furthermore, the resulted nanotube arrays are expected to have bright application prospects for solar utilization.

The title reaction affords a series of fully functionalized pyrrole derivatives (III) and (V) via rhodium azavinyl carbene intermediates.

Hydroquinine anthraquinone-1,4-diyl diether [(DHQ)(2)AQN]-catalyzed unprecedented asymmetric domino annulation reactions of acylidenoxindoles/isatins, acylidenoxindoles and allenoates are disclosed in this communication, providing a facile access to hexahydrofuro[2,3-b]furans containing four contiguous chiral centers in good to excellent yields along with good to excellent ee values and moderate to good dr values. Based on theoretical investigations, a concerted [3+2] ring-closure process was proposed, in which steric hindrance and pi-pi stacking interaction between catalyst and substrate subtly co-control the diastereoselectivity of the reaction.

The chemoselective [4+2] vs. [2+2] cycloaddition between allenoates and dithioesters can be controlled by switching the nucleophilic amine catalyst. The two modes of cyclizations represent the first example of controllable and chemoselective annulations between allenoates and dienophiles catalyzed by amine. These cyclizations are useful in offering a divergent synthesis of sulfur-containing heterocycles. On the basis of this investigation, it can be realized that dithioesters with a vicinal electron-withdrawing group can react not only like a Michael acceptor but also as a ketone or imine.

Rh(II)-catalyzed intermolecular [3+2] cycloaddition of 2 H-azirines with N-sulfonyl-1,2,3-triazoles is disclosed, in which a series of fully functionalized pyrroles is produced via rhodium azavinyl carbene intermediates. A distinct feature of this reaction is that the azavinyl carbene serves as a [2 C] equivalent, instead of as [1 C] or aza-[3 C] synthons, which have been reported previously in cyclopropanations and [3+n] cycloadditions. Moreover, this methodology has also been successfully applied in the total synthesis of URB447 as well as the formal synthesis of Atorvastatin (Lipitor).

The first example for the preparation of enantioenriched azo compounds from hydrazones and Morita–Baylis–Hillman adducts has been developed, affording azo compounds incorporating an oxindole scaffold in up to 91% yield along with a 93% ee value under the catalysis of (DHQ)2AQN.

This novel three component reaction gives an easy access to isoquinoline derivatives via a 1,4-dipolar cycloaddition reaction.

One-pot thermal-induced [3+2] cycloaddition/silica gel-promoted fragmentation sequence between isatin ketonitrones and electron-deficient alkynes affords spiro[indoline]oxindoles in moderate to excellent yields along with good diastereoselectivities. The detailed mechanism of silica gel-promoted fragmentation has been clarified by experiment and DFT calculations.

The first example of the intramolecular [3 + 3] cycloaddition of ketone-derived nitrones (I) and cyclopropanes (II) is described.

Yb(NTf(2))(3)-catalyzed [3 + 3] cycloaddition between isatin ketonitrones and cyclopropanes is described. A variety of spiro[tetrahydro-1,2-oxazine]oxindoles were obtained in moderate to good yields along with good regioselectivities. This is the first example of the intermolecular [3 + 3] cycloaddition between ketone-derived nitrones and cyclopropanes.

Gallium nitride crystals in nano-scale have been fabricated by dc arc plasma method using gallium and N2+NH3 as starting materials. Transmission electron microscope, selected area diffraction and x-ray diffraction investigation of the as-grown GaN crystals show that the well faceted crystals are single crystalline GaN in wurtzite structure having lattice constants ao = 3.18 A and co = 5.18 A.