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A visible-light-induced photocatalytic strategy for the synthesis of flavonoids has been developed through the deoxygenative/cyclization reaction of salicylic acid derivatives with aryl acetylene using diphenyl sulfide as an O-transfer reagent. Based on the controlled experiments, the mechanism of visible-light-induced free radical coupling cyclization was proposed. The protocol obtained 51 flavonoids in good yields and has been successfully applied to the synthesis of some natural flavones.

The gelatinization temperature (GT) of endosperm starch influences rice eating and the cooking quality (ECQ). ALK encoding soluble starch synthase IIa (SSIIa) is the major gene determining grain GT in rice. Herein, we identified a spontaneous ALK mutant named ALKd, which resulted from a G/T single-nucleotide polymorphism (SNP) in exon 1 of the ALKc allele from the high-GT indica rice cultivar. Compared with grains from the ALKc near-isogenic line (NIL), NIL(ALKd) grains exhibited a high GT (2.3 °C) and improved retrogradation properties. The NIL(ALKd) grain starch contained an increased proportion of amylopectin intermediate chains (DP 13-24) at the expense of short chains (DP < 12), resulting in enhancements in both the crystallinity and the lamellar peak intensity compared with low-GT rice grains. Moreover, both NIL(ALKd) and NIL(ALKc) grains also featured a significantly lower apparent amylose content (AAC), harder gel consistency (GC), higher pasting curve, and poorer taste values in comparison to Nip(ALKa) grains. Taken together, this work provides novel insights underlying the allelic variation of the ALK gene in rice.

Obtaining genetic variation information from indica rice hybrid parents and identification of loci associated with heterosis are important for hybrid rice breeding. Here, we resequence 1,143 indica accessions mostly selected from the parents of superior hybrid rice cultivars of China, identify genetic variations, and perform kinship analysis. We find different hybrid rice crossing patterns between 3- and 2-line superior hybrid lines. By calculating frequencies of parental variation differences (FPVDs), a more direct approach for studying rice heterosis, we identify loci that are linked to heterosis, which include 98 in superior 3-line hybrids and 36 in superior 2-line hybrids. As a proof of concept, we find two accessions harboring a deletion in OsNramp5, a previously reported gene functioning in cadmium absorption, which can be used to mitigate rice grain cadmium levels through hybrid breeding. Resource of indica rice genetic variation reported in this study will be valuable to geneticists and breeders., Hybrid rice cultivars are widely planted around the world. Here, the authors resequence 1,143 indica accessions, focusing on the parents of superior hybrid rice lines in China, and reveal genetic loci that are associated with heterosis via measuring frequency of parental variation difference (FPVD).

A visible light-induced decarboxylative alkylation of heterocyclic aromatics with aliphatic carboxylic acids was developed by using anthocyanins as a photocatalyst under mild conditions. A series of alkylated heterocyclic compounds were obtained in moderate to good yields by using the metal-free decarboxylative coupling reaction under blue light. This strategy uses cheap and readily available carboxylic acids as alkylation reagents with good functional group tolerance and environmental friendliness. It is worth noting that this is the first time that anthocyanin has been used to catalyze the Minisci-type C-H alkylation. The mechanism of decarboxylation alkylation was studied by capturing the adduct of alkyl radical and hydroquinone, thus confirming a radical mechanism. This protocol provides an alternative visible light-induced decarboxylative alkylation for the functionalization of heterocyclic aromatics.

A bis-quinoline-2-carboxylic acid copper salt as a single crystal was prepared and characterized by X-ray single crystal analysis. The crystal as a catalyst was applied to the Mizoroki–Heck coupling reaction between arylboronic acids and α-olefins. A series of diarylethenes and aryl olefins were synthesized with good to excellent yields at room temperature. The catalytic system exhibited good functional group tolerance and low pollution. A bis-quinoline-2-carboxylic acid copper salt as a single crystal was prepared and characterized by X-ray single crystal analysis. The crystal as a catalyst was applied to the Mizoroki–Heck coupling reaction between arylboronic acids and α-olefins .

A series of naphthalene bridged bis-triphenylamine derivatives with a twisted structure was designed, synthesized and characterized. The dependence of their thermal, photophysical and electrochemical properties and performance as emitters in OLEDs on their chemical structure was systematically studied by the introduction of aryl groups with electron-donating or electron-withdrawing substituents to the naphthalene bridged bis-triphenylamine core. These compounds exhibited steady blue light emissions and high Td values ranging from 468 to 500 °C. Most importantly, the deep-blue OLEDs were successfully fabricated using a solution processed method by blending PVK and PBD to improve OLED performance. The optimal device E exhibited a very high luminance of 10 407 cd m−2 and a maximum current efficiency of 7.80 cd A−1 with CIE coordinates of (0.166, 0.097). These results indicated that these compounds with the twisted naphthalene bridged bis-triphenylamine core could show stable deep-blue electroluminescence properties and introducing the electron-donating group (–OCH3) could enable high luminance and current efficiency for OLEDs.

A new protocol for the Cu(OAc)2-mediated cyanation of arenes using benzimidazole as the directing group with 2-(4-methylpiperazin-1-yl)acetonitrile as the cyano source was developed. A series of cyano derivatives were facilely and conveniently obtained in moderate to good yields by using this method. The C–H activation catalytic system was originally applied to the C(sp2)–H cyanation of the aryl/heteroaryl to synthesize 2-(1H-benzo[d]imidazol-2-yl)aryl nitriles. There were 19 new compounds in the synthesized 20 cyanide products. In this reaction, 2-(4-methylpiperazin-1-yl)acetonitrile as the cyano source was originally employed in the C(sp2)–H cyanation of the arenes. In addition, a fluorescent material 5a was obtained by derivative reactions of the obtained cyanide product 3.

A series of DBU-based (DBU = 1, 8-diazabicyclo [5.4.0] undec-7-ene) dicationic ionic liquids with different anions were successfully synthesized by the reaction of DBU and 1, 6-dichlorohexane. Therein, the dicationic ionic liquid 1, 1′-(hexane-1, 6-diyl)bis(1, 8-diazabicyclo [5.4.0]undec-7-enium) dichlorine (IL-1) was successfully employed as an efficient catalyst in esterification reaction of carboxylic acids with primary chloroalkanes under mild conditions without any additional basic reagents. Moreover, the optimum catalyst could be efficiently reused for five times without any significant change on the catalytic effect. The improved protocol is not only efficient, but also green and pollution-free.

A novel nickel(II) naringenin-oxime complex was designed, synthesized and characterized. Therein, the nickel(II) naringenin oxime complex as an efficient catalyst was used in Mizoroki–Heck coupling reactions of aryl halides containing electron-rich and electron-deficient substituents with styrene, methyl acrylate and divinylbenzene (DVB), respectively. The reaction proceeded efficiently under alkaline conditions in the presence of 0.30 mol% of the Ni(II) naringenin oxime complexand N2H4·H2O as the reductant in EtOH at 80 °C, and 32 alkene products were afforded in moderate to excellent yields, containing four new olefins. The new catalytic system not only provided an inexpensive and efficient process with greener conditions, but also broadened the reaction scope.

A series of N,O-bidentate ligands were synthesized using the Vilsmeier–Haack reaction and oximation. 2,5-Dihydroxyterephthalaldehyde dioxime (L8) as an efficient N,O-symmetrical bidentate ligand was prepared from hydroquinone. It was studied as a high activity ligand for palladium-catalyzed Suzuki–Miyaura cross-coupling reactions of aryl chlorides with arylboronic acids under mild conditions. The coupling reactions were performed in the presence of PdCl2 as the catalyst, L8 as the ligand, Na2CO3 as the base, PEG-400 as the PTC and in ethanol/water (1 : 1) as an environmentally benign solvent at 85 °C. Plentiful biaryls were obtained by the optimized reaction with good yields at a low palladium loading of 0.20 mol%.

A sustainable and efficient catalyst for converting carbohydrates to a renewable platform chemical 5-hydroxymethylfurfural (HMF) is the goal in the study of biomass recycling. Reduced graphene oxide-supported tungsten trioxide (WO3/RGO) as an acidic catalyst was synthesized through a one-step hydrothermal method, characterized via TEM, XPS, XRD and Raman spectroscopy and applied to the conversion of fructose to HMF. The WO3/RGO catalyst showed a highly efficient catalytic activity, and the yield of HMF could reach up to 84.2% with complete conversion of fructose. The catalyst could be reused five times with a slight decrease in activity. Further study indicated that WO3/RGO could also catalyze the conversion of cellulose, glucose and sucrose to HMF.

A bidentate-chelation assistant palladium-catalyzed direct C-H cyanation of picolinamides with TMSCN is described. The reaction of various derivatives gave the corresponding cyanated products in moderate to good yields under mild conditions. In addition, the cyanated product could transform into some valuable functional groups in good yields. Copyright © 2016 John Wiley & Sons, Ltd.

A mild and efficient palladium-catalyzed decarboxylative ortho-aroylation of N-acetyl-1,2,3,4-tetrahydroquinolines with α-oxoarylacetic acids via C–H bond activation is described. This protocol provides access to a series of C8-aroyl terahydroquinolines.

As an outstanding mesh catalyst support, reduced graphene oxide (RGO) has attracted enormous attention in recent years. Cu nanoparticles-RGO (Cu NPs@RGO) as a green catalyst was prepared through a green reduction method by ascorbic acid in N-methyl-2-pyrrolidone. The structure of prepared Cu NPs@RGO was characterized. The catalytic activity of Cu NPs@RGO was estimated. A green and efficient method for synthesizing symmetrical biaryl compounds was developed by Cu NPs@RGO-catalyzed Ullmann homocoupling of aryl halides or arylboronic acids in ionic liquids under microwave (MW) irradiation. The catalytic system could be recycled five times with slight loss of activity. Through this method, nine kinds of biaryls were prepared by homocoupling reaction of the corresponding aryl iodides, aryl bromides, aryl chlorides and aryl boronic acids in moderate to good yields.

An efficient strategy for the nickel-catalysed synthesis of biaryls and terphenyls has been developed in environmentally-friendly reaction media. In the presence of β-diketone and PPh3 ligands, Ni(TFA)2 acted as an effective catalyst for the Suzuki–Miyaura cross-coupling of aryl halides and arylboronic acids in an ionic liquid solution. Biaryls and terphenyls were obtained in good yields under this catalytic system.

The efficient, simple, and environment-friendly route of direct cyanation of picolinamides has been developed with nontoxic K4[Fe(CN)6] as the cyanide source through Pd-catalyzed C–H bond activatio...

A radioactive metallofullerene 177LuxLu(3−x)N@C80 was firstly synthesized by means of neutron irradiation on Lu3N@C80. After modification by methoxypolyethylene glycol amine, in vivo investigation on tumor-bearing mice was performed. The results reveal favorable affinity toward tumors, suggesting that the obtained 177LuxLu(3−x)N@C80–PCBPEG could be promising for tumor diagnosis and therapy.

A total synthesis method for protosappanin A, which is a complex natural product with many biological activities, was developed with 6 linear steps. Dibenzo[b,d]oxepinones as the key intermediates of the synthetic route were prepared by a palladium-catalyzed ortho C-H activation/C-C cyclization under microwave irradiation. 25 derivatives of protosappanin A were obtained.

Pd/C-catalyzed Suzuki–Miyaura cross-coupling between aryl bromides and arylboronic acids in 50% methanol aqueous solution proceeded smoothly in the presence of 18-crown-6. Various aryl bromides bearing electron-withdrawing groups and electron-donating groups coupled with arylboronic acid in high yields. In addition, the catalyst could be recycled five times without loss of activity. Copyright © 2012 John Wiley & Sons, Ltd.

Comparative experiments have been performed to investigate the degradation efficiency of nitrobenzene and the removal efficiency of TOC in aqueous solution bythe processes of ceramic honeycomb supported different metals (Fe, Ni, and Zn) catalytic ozonation, indicating that the modification with metals can enhance the activity of ceramic honeycomb for the catalytic ozonation of nitrobenzene, and the loading percentage of metal and the metallicity respectively presents a positive influence on the degradation of nitrobenzene. The degradation efficiency of nitrobenzene is determined by the initiation of hydroxyl radical (*OH) according to a good linear correlation in all the processes of modified ceramic honeycomb catalytic ozonation at the different loading percentages of metals. The modification of ceramic honeycomb with metals results in the conversion of the pH at the point of zero charge (pHpzc) and the evolution of surface groups. Divergence from the conventional phenomenon, the enhancement mechanism of ozone decomposition on the modified ceramic honeycomb with metals is proposed due to the basic attractive forces of electrostatic forces or/and hydrogen bonding. Consequently, a novel relationship between the initiation of *OH and the surface-OH2+ group on the modified catalyst is established based on the synergetic effect between homogeneous and heterogeneous reaction systems.

The use of cordierite or Cu-cordierite for heterogeneous catalytic ozonation enhances significantly the degradation efficiency and the TOC removal of nitrobenzene in aqueous solution relative to ozonation alone, owing to the synergistic effect between ozone and the catalysts, and the modification process with Cu can increase the catalytic activity of cordierite forthe ozonation of nitrobenzene. The adsorption of nitrobenzene is too small to make a significant contribution to the degradation of nitrobenzene in either of the processes of catalytic ozonation. The initiation of hydroxyl radical (*OH) improves as the amount of Cu-cordierite catalyst is increased, meaning that the degradation of nitrobenzene is mainly attributed to *OH oxidation. The modification by loading Cu increases the density of surface hydroxyl groups and the pH at the point of zero charge (pH(PZC)) of raw cordierite. The investigation of the enhancement mechanism confirms that the modification by loading Cu causes changes of density of surface hydroxyl groups, pH(PZC), and /pH - pH(PZC)/, resulting in the acceleration initiation of *OH which can promote the degradation of nitrobenzene. The result shows that the optimal critical loading percentage of Cu is 3% under the present experimental conditions.

The influences of initial pH on the degradation efficiency of nitrobenzene in aqueous solution were investigated with a semicontinuous batch reactor in the processes of ozone alone, ozone/ceramic honeycomb, and adsorption of ceramic honeycomb. The results indicated that initial pH significantly affected the concentrations of offgas, residual ozone, and the utilization efficiency of ozone. The experiments also detected the generation of hydroxyl radicals (*OH), the removal of TOC, and the formation and evolution of byproduct at different initial pHs in the ceramic honeycomb catalytic ozonation process. It was found that the systems of different initial pHs exhibited the different extent of the conversion of pH, the leaching of effective components, and the establishment of pH at the point of zero charge (pH(PZC)) in the catalytic oxidation process. The experimental findings presented a good correlation between initial pH and terminal pH and the establishment of pHpzc with terminal pH, and indicated the relationship between the absolute value of the difference between terminal pH and terminal pH(PZC) (A) and the density of surface hydroxyl groups. Based on the correlation between the density of surface hydroxyl groups in the neutral state and A, possible mechanism of influence of initial pH on the degradation of nitrobenzene in aqueous solution by ceramic honeycomb catalytic ozonation was proposed, suggesting that the conversion of initial pH determines the establishment of pHpzc, and the synergistic effect of pH terminal and pHpzc terminal affects the density of surface hydroxyl groups in the neutral state, which controls the concentration of *OH, determining the degradation of nitrobenzene and the formation of byproduct.

In the title compound, {[Co(C10H14N4)2(H2O)2]Cl2·4H2O}n, the CoII atom and the mid-point of the 1,1′-butane-1,4-diyl­diimidazole ligands lie on inversion centers. The CoII atom is six-coordinated in a slightly distorted octa­hedral environment by four N atoms from four different ligands and by two O atoms from the water mol­ecules. The CoII atoms are bridged by the ligands into a (4,4) net. Adjacent nets are linked to the chloride anions and uncoordinated water mol­ecules via O—H⋯Cl and O—H⋯O hydrogen bonds, generating a three-dimensional supra­molecular structure.

In the title compound, {[Co(C(10)H(14)N(4))(2)(H(2)O)(2)](NO(3))(2)}(n), the Co(II) ion lies on an inversion center and is six-coordinated in an octa-hedral environment by four N atoms from four different 1,1'-butane-1,4-diyldiimidazole ligands and two O atoms from the two water mol-ecules. The Co(II) atoms are bridged by ligands, generating a two-dimensional (4,4)-network. Adjacent fishnet planes are linked to the nitrate anions via O-H⋯O hydrogen bonds, forming a three-dimensional supra-molecular structure.

The title compound, C(14)H(13)NO(4), was prepared through a palladium-catalysed Suzuki-Miyaura coupling reaction. The asymmetric unit comprises two mol-ecules related by pseudo-inversion symmetry. The dihedral angles between the benzene rings in the two mol-ecules are 44.30 (6) and 48.50 (6)° while those between the benzene ring and the nitro group are 6.54 (13) and 5.73 (10)°. The crystal packing is defined only by Van der Waals inter-actions.

The title compound, C15H13NO2, was prepared through a palladium-catalysed Suzuki–Miyaura coupling reaction. The dihedral angle between the biphenyl rings is 40.96 (6)°. The methoxy groups are twisted slightly out of the plane of the benzene ring [C—C—C—C torsion angles = −3.61 (18) and 12.6 (2)°]. The packing of the molecules is stabilized by van der Waals interactions.

The title compound, C17H16O5, was prepared through a cyclization reaction of 2-(3′,4′,5-trimethoxybiphenyl-2-yloxy)acetyl chloride. The two benzene rings form a dihedral angle of 34.55 (5)°. The crystal structure does not feature any hydrogen bonds.

The title compound, C13H10N4O2S, was prepared through a cyclization reaction of 1,10-phenanthroline-5,6-dione and thiourea. The dihedral angle between the pyridine rings is 8.22 (2)°. In the crystal, molecules are connected by N—H...O, O—H...N, N—H...S and O—H...S hydrogen bonds, forming a three-dimensional network.

The title compound, C(14)H(10)F(3)NO(3), was prepared by a palladium-catalysed Suzuki-Miyaura coupling reaction. The dihedral angle between the nitro group and its parent benzene ring is 66.85 (19)° while the dihedral angle between the two benzene rings is 49.98 (9)°. The CF(3) group is disordered over two sets of sites with occupancies of 0.457 (8) and 0.543 (8).

The title compound, C9H9NO6S, was prepared by the reaction of methanol and thionyl chloride with 4-methylsulfonyl-2-nitrobenzoic acid under mild conditions. The dihedral angle between the nitro group and benzene ring is 21.33 (19)° and that between the carboxylate group and the benzene ring is 72.09 (17)°. The crystal structure is stabilized by weak intermolecular bifurcated C—H...O interactions occurring in the (100) plane.

In the molecular structure of the title compound, C11H15N3O5S, the amide group is nearly perpendicular to the pyridine ring, making a dihedral angle of 86.30 (13)°. The terminal ethyl group is disordered over two sites of equal occupancy. Intermolecular N—H...O hydrogen bonding is present in the crystal structure.

In the title compound, [Co(C8H6NO6S)(C12H8N2)(H2O)3](C8H6NO6S)·H2O, the CoII atom shows an octa­hedral coordination, the geometry being defined by a carboxylate O atom from a 4-nitro­phenyl­sulfonyl­acetate anion, two N atoms from the phenanthroline ligand and three water mol­ecules. The mol­ecules of the complex are linked by O—H⋯O hydrogen bonds, which also involve the solvent water mol­ecule, to form a linear chain structure.

In the title coordination polymer, [Co(C8H6ClO3S)2(C10H8N2)(H2O)2]n, the CoII atom exists in an octa­hedral coordination environment formed by two carboxylate O atoms from two (4-chloro­phenyl­sulfin­yl)acetate ligands, two N atoms from bipyridine ligands and two water mol­ecules. The CoII atom lies on a twofold rotation axis. Bridging by the bipyridine ligand leads to a linear chain structure, and inter­molecular O—H⋯O hydrogen bonds link the chains into a three-dimensional network.

In the ionic title compound, [Ni(H2O)6](C8H6NO5)2·5H2O, the [Co(H2O)6]2+ cation, (4-nitro­phen­oxy)acetate anions and water mol­ecules engage in O—H⋯O hydrogen bonding, generating a three-dimensional hydrogen-bonded network.

In the title coordination polymer, [Zn(C8H6NO5S)2(C10H8N2)(H2O)2]n, each ZnII ion is in a slightly distorted octa­hedral coordination environment, formed by two carboxy­late O atoms from two (4-nitro­phenyl­sulfin­yl)acetate ligands, two N atoms from bipyridine ligands and two water mol­ecules. The ZnII ions and the bipryidine ligands lie on crystallographic twofold axes with the ZnII ions linked by bipyridine ligands into a one-dimensional chain structure. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds link one-dimensional chains into a three-dimensional network.

The title compound, [Cd(C8H6NO4S)2(H2O)3]·2H2O, has a seven-coordinate CdII atom in a distorted penta­gonal–bipyramidal geometry defined by four carboxylate O atoms from two (2-nitro­phenyl­sulfan­yl)acetate groups and three O atoms from three water mol­ecules. The complex mol­ecules are linked together by inter­molecular hydrogen bonds involving the uncoordinated water mol­ecules, resulting in a two-dimensional network.