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A series of o-phenylenediamine bridged tris(phenolate) ligand-stabilized rare-earth metal complexes were synthesized and characterized. Lanthanum (complex 1), neodymium (complex 2tBu), and yttrium (complex 3) complexes stabilized by ligand of bulky tert-butyl substituents are mononuclear, whereas neodymium complexes 2Me and 2Cl bearing smaller methyl and chloro substituents are dinuclear, respectively. They were applied in the alternating copolymerization of CO2 and cyclohexene oxide. The addition of benzyl alcohol is beneficial to improving yields (up to 86%) and selectivity of poly(carbonate) (up to 99%). Stoichiometric reaction of benzyl alcohol with rare-earth metal complexes 1 and 2tBu results in formation of complexes 4 and 5 as dinuclear complexes with benzyl alcohol coordination, which was confirmed via single crystal X-ray diffraction analysis, and nuclear magnetic resonance (NMR) spectroscopy (for 4). Complex 5 shows equally good activity and selectivity of that of complex 2tBu and benzyl alcohol, consolidating that complex 5 is indeed generated during polymerization. The neodymium tris(phenolate) 5 is one of the few examples of rare-earth metal complex as a single-component initiator for copolymerization of epoxide and CO2. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry analysis proves benzyloxy group as the chain end. 1H NMR monitoring suggests that the insertion of CO2 may be the first step in the growth of the polymer chain.

Neodymium complexes were synthesized and employed as efficient initiators for the random copolymerization of TMC and l-LA under mild conditions.

Four homodinuclear rare earth metal (RE) complexes 1-4 bearing a multidentate diglycolamine-bridged bis(phenolate) ligand were synthesized. In addition, seven heterobimetallic RE-Zn complexes 5-11 were prepared through a one-pot strategy. In these heterobimetallic complexes, two RE centers are bridged by either Zn(OAc)2 or Zn(OBn)2 moieties. All complexes were characterized by single crystal X-ray diffraction, elemental analysis, IR spectroscopy, and multinuclear NMR spectroscopy (in the case of diamagnetic complexes 1, 4, 7 and 11). Moreover, the multi-nuclear structures of complexes 4 and 11 in solution were also studied by 1H DOSY spectroscopy. These complexes were applied in catalyzing the coupling reaction of carbon dioxide (CO2) with epoxides. Zn(OAc)2- and Zn(OBn)2-bridged heterobimetallic complexes showed comparable catalytic activities under ambient conditions and were more active than monometallic RE complexes. Significant synergistic effect in heterobimetallic complexes is observed. Mono-substituted epoxides were converted into cyclic carbonates under 1 atm CO2 at 25 °C in 88-96% yields, whereas di-substituted epoxides reacted under 1 atm CO2 at higher temperatures in 40-80% yields.

Plant proteins are suitable and alternative to fish meals (FMs), with less cost compared with that of all other types of fish feeds. In recent years, soy protein concentrate (SPC) has emerged as a cost-effective alternative to FM; however, little is known regarding the effects of dietary SPC on general fish physiology and well-being. This study aimed to perform comprehensive physiological and transcriptomic analysis for testing the applicability of SPC as fish feeds in hybrid grouper (Epinephelus fuscoguttatus♀ × E. lanceolatus♂) [SPC replaced 0% (CK), 30% (SPC30), and 75% (SPC75) of FM protein]. Generally, SPC30 promoted fish survival and had less effects on the phenotype, while SPC75 reduced fish survival, promoted inflammation, and regulated multiple physiological responses. Thousands of differentially expressed genes (DEGs) by SPC were identified in the intestine, liver, and muscle, which were enriched in biological regulation, cellular process, metabolic process, single-organism process, cell, cell part, membrane, binding, and catalytic activity based on RNA-seq. Notably, some DEGs involved in amino acid and lipid metabolism in the digestive system highlighted the modulatory effect of SPC on these metabolic processes, consistent with the physiological responses including enzyme activities. The enriched aspects of these predominant DEGs might be directly related to the different effects of SPC30 and SPC75 on fish growth, digestibility, and underlying enzyme activities and histology. In conclusion, the comprehensive physiological and transcriptomic comparative analysis of CK, SPC30, and SPC75 was also effective in testing the applicability of SPC as fish feeds and in designing a proper diet with the best impact on the growth performance and health of fish in hybrid grouper.

A series of rare-earth (RE) metal complexes (Y, Sm, Nd, and La) stabilized by polydentate N-methylethylenediamine-bridged tris(phenolato) ligands was synthesized and characterized. Lanthanum comple...

Gonadotropin-releasing hormone (GnRH) is a key neuropeptide of the reproductive system. However, little is known about the role of GnRH in the spotted scat (Scatophagus argus). Here, three GnRH subtypes (cGnRH-II, sGnRH, and sbGnRH) were identified in the spotted scat. cGnRH-II and sGnRH were only expressed in the brains and gonads of both male and female fish, exhibiting a tissue-specific expression pattern, while sbGnRH was expressed at different transcription levels in all examined tissues. During ovarian maturation, hypothalamus-associated sbGnRH was upregulated, while the expression of sGnRH was variable and cGnRH-II first increased and then decreased. In vivo experiments showed that sbGnRH significantly promoted the expression of fsh and lh genes in a dose-dependent manner and exhibited a desensitization effect on lh expression at high concentrations. For sGnRH and cGnRH-II, only high concentrations could induce fsh and lh expression. Furthermore, treatment with highly concentrated sbGnRH peptide also induced fsh and lh expression, whereas the sGnRH and cGnRH-II peptides only induced fsh expression in vitro. 17β-Estradiol (E2) significantly inhibited the expression of sbGnRH mRNA in a dose-dependent manner and did not impact sGnRH and cGnRH-II mRNA levels in vivo or in vitro. The inhibitory effect of E2 on sbGnRH expression was attenuated by the estrogen receptor (ER) broad-spectrum antagonist (fulvestrant) and the ERα-specific antagonist (methyl-piperidinopyrazole), respectively, implying that the feedback regulation on sbGnRH is mediated via ERα. This study provides a theoretical basis for the reproductive endocrinology of the spotted scat by studying GnRH.

A series of lanthanide alkoxo complexes supported by ONNO salalen ligands were synthesized and characterized. A one-pot reaction of LH

Developing catalysts that are capable of catalyzing the copolymerization of e-caprolactone and L-lactide to give random CL/LA copolymers is of great importance. One-pot reaction of La[N(SiMe3)2]3 with 1 equiv. of LH2 (LH2 = NH(CH2CH2NCHC6H2-3,5-tBu2-2-OH)2) in THF at room temperature, followed by protolysis with one equivalent amount of ROH (R = C6H2-2,6-tBu2-4-CH3, tBu, iPr, Bn, and Et) at 60 °C gave the mono-Schiff-base-ligated lanthanum aryloxide complex LLa(OC6H2-2,6-tBu2-4-CH3)(THF) (1), and lanthanum alkyloxide complexes LLaOtBu(THF) (2), [LLaOiPr]2 (3), [LLaOBn]2 (4), and [LLaOEt]2 (5) in 59–69% isolated yields. These lanthanum complexes were capable of initiating the homopolymerization of L-lactide and rac-lactide with extremely high activity, and the copolymerization of e-caprolactone (e-CL) and L-lactide (L-LA) to give statistical CL/LA copolymers via a transesterification reaction.

The wild populations of the commercially valuable ornamental fish species, Betta splendens, and its germplasm resources have long been threatened by habitat degradation and contamination with artificially bred fish. Because of the lack of effective marker resources, population genetics research projects are severely hampered. To generate genetic data for developing polymorphic simple sequence repeat (SSR) markers and identifying functional genes, transcriptomic analysis was performed. Illumina paired-end sequencing yielded 105,505,486 clean reads, which were then de novo assembled into 69,836 unigenes. Of these, 35,751 were annotated in the non-redundant, EuKaryotic Orthologous Group, Swiss-Prot, Kyoto Encyclopedia of Genes and Genomes and Gene Ontology databases. A total of 12,751 SSR loci were identified from the transcripts and 7970 primer pairs were designed. One hundred primer pairs were randomly selected for PCR validation and 53 successfully generated target amplification products. Further validation demonstrated that 36% (n = 19) of the 53 amplified loci were polymorphic. These data could not only enrich the genetic information for the identification of functional genes but also effectively facilitate the development of SSR markers. Such knowledge would accelerate further studies on the genetic variation and evolution, comparative genomics, linkage mapping and molecular breeding in B. splendens.

We demonstrated a mode-locked fiber laser based on a novel photonic device that combined optical microfiber coupler (OMC) and saturable absorption materials. The stable ultrafast laser was formed based on the interaction between the deposited Indium Antimonide (InSb) and the evanescent field on OMC. Different from optical microfiber (OM), OMC can directly output the mode-locked laser without additional beam splitting devices, which further improves the integrated characteristics of the fiber laser. The pulse duration of the output pulse is 405 fs at the central wavelength of 1560 nm. To the best of our knowledge, this is the first time that optical microfiber coupler based saturable absorber (OMC-SA) for mode-locked fiber laser is demonstrated.

The spotted scat (Scatophagus argus) is an economically important cultured marine fish that exhibits a typical sexual size dimorphism (SSD). SSD has captivated considerable curiosity for farmed fish production, however, up till now the exact underlying mechanism remains largely unclear. As an important digestive and metabolic organ, the liver plays key roles in the regulation of fish growth. It is necessary to elucidate its significance as a downstream component of the hypothalamic-pituitary-liver axis in the formation of SSD. In this study, the liver physiological differences between the sexes were evaluated in S. argus, and the activity of several digestive and metabolic enzymes were affected by sex. Females had higher amylase, protease, and glucose-6-phosphate dehydrogenase activities, while males exhibited markedly higher hepatic lipase and antioxidant enzymes activities. A comparative transcriptomics was then performed to characterize the responsive genes. Illumina sequencing generated 272.6 million clean reads, which were assembled into 79,115 unigenes. A total of 259 differentially expressed genes were identified and a few growth-controlling genes such as igf1 and igfbp1 exhibited female-biased expression. Further analyses showed that several GO terms and pathways associated with metabolic process, particularly lipid and energy metabolisms, were significantly enriched. The male liver showed a more active mitochondrial energy metabolism, implicating an increased energy expenditure associated with reproduction. Collectively, the female-biased growth dimorphism of S. argus may be partially attributed to sexually dimorphic metabolism in the liver. These findings would facilitate further understanding of the nature of SSD in teleost fish.

Four homodinuclear rare earth metal (RE) complexes 1-4 bearing a multidentate diglycolamine-bridged bis(phenolate) ligand were synthesized. In addition, seven heterobimetallic RE-Zn complexes 5-11 were prepared through a one-pot strategy. In these heterobimetallic complexes, two RE centers are bridged by either Zn(OAc)

A nonmetal catalyst [Ph3C][B(C6F5)4] has been developed to catalyze hydroarylation reaction of alkenes with aromatic primary, secondary, and tertiary amines, which generated aniline derivatives in 32–98% yields. This method is applicable to a wide range of substrates, is highly chemo- and regioselective, and provides a simple and efficient approach for aniline derivative preparation.

A series of novel salan-ligated rare-earth metal amide complexes were prepared and employed as initiators for the ROP of rac-β-butyrolactone (rac-BBL). Tuning the substituents on the N atoms of the ligand frameworks from aromatic groups to aliphatic groups results in switching tacticity from iso-tactic to syndio-tactic in rac-BBL polymerization.

Several aluminium alkyl and alkyloxide complexes supported by a thioether-bridged salen ligand were synthesized by the protonolysis reaction. Reactions of N,N’-bis(3,5-di-tert-butylsalicylidene)-2,2’-diaminophenylsulfide (H2L) with one or two equivalents of AlMe3 in toluene at 100 °C afforded the corresponding mono- and binuclear aluminium methyl complexes LAlMe (1) and L(AlMe2)2 (2). Treatment of the in situ generated complex 1 with one equivalent of ROH (R = PhCH2, iPr, CH3OCH2CH2) produced the desired aluminium alkyloxide complexes LAlOCH2Ph (3), LAl(OiPr) (4) and LAlO(CH2)2OCH3 (5). All the molecular structures were established by single crystal X-ray diffraction studies. It was found that aluminium alkyloxide complexes 3-5 showed higher catalytic activity for the homopolymerization of e-caprolactone (e-CL) than corresponding aluminium methyl complexes 1 and 2. Furthermore, these alkyloxide complexes were also efficient initiators for the copolymerization of L-lactide and e-CL to give practically random copolymers.

In this work, the new calcium-magnesium-silicate Ca5MgSi3O12 ceramic was made via traditional solid-state reaction. The bioactivities were investigated by immerging the as-made ceramics in simulated body fluid (SBF) for different time at body temperature (37 °C). Then the samples were taken to measure X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), X-ray energy-dispersive spectra (EDS), and Fourier transform infrared spectroscopy (FT-IR) measurements. The bone-like hydroxyapatite nanoparticles formation was observed on the ceramic surfaces after the immersion in SBF solutions. Ca5MgSi3O12 ceramics possess the Young’s modulus and the bending strength and of 96.3 ± 1.2 GPa and 98.7 ± 2.3 MPa, respectively. The data suggest that Ca5MgSi3O12 ceramics can quickly induce HA new layers after soaking in SBF. Ca5MgSi3O12 ceramics are potential to be used as biomaterials for bone-tissue repair. The cell adherence and proliferation experiments are conducted confirming the reliability of the ceramics as a potential candidate.

Several lanthanide complexes supported by N-aryl substituted β-ketoiminato ligands were synthesized by the protonolysis reaction. Reactions of 1-phenyl-3-N-(p-methoxyphenylimino)-1-butanone (HL) with Ln[N(SiMe3)2]3 and Ln(OAr)3(THF) (ArO = 2,6-But2-4-MeC6H2O) in a 2:1 M ratio gave mononuclear lanthanide amides L2Ln[N(SiMe3)2] [Ln = Y (1), Sm (2), Nd (3)] and aryloxides L2Ln(OAr) [Ln = Y (4), Nd (5)], respectively, whereas the same reaction with Yb[N(SiMe3)2]3 afforded an unexpected homoleptic ytterbium complex L3Yb (6). The solid-state structures of lanthanide complexes 1–6 were determined by single-crystal X-ray diffraction. It was found that complexes 1–5 can efficiently initiate the ring-opening of rac-lactide in THF to afford hetereotactic-rich polylactides.

Four rare-earth metal complexes supported by Salpn ligand were synthesized, and their catalytic behaviors for the polymerization of rac -lactide ( rac -LA) were explored. The amine elimination reactions of Salpn ligand LH 2 (LH 2 = (CH 2 ) 3 [N = CH(C 6 H 4 -2-OH)] 2 ) with RE[N(SiMe 3 ) 2 ] 3 (RE = Y, Yb, Sm, Nd) in a 1:1 M ratio, and then with 1 equiv. of phenol ArOH (ArO = 2,6-Bu t 2 -4-MeC 6 H 2 O) in THF gave the trinuclear rare-earth metal aryloxo complexes [LRE(OAr)(HMPA)] 3 (RE = Y ( 1 ), Yb ( 2 ), Sm ( 3 )), and the mononuclear neodymium complex LNd(OAr)(HMPA) 2 ( 4 ), respectively, in good yields in the presence of HMPA (HMPA = hexamethylphosphoric triamide). Complexes 1 and 2 can also be prepared by the phenol elimination reactions of (ArO) 3 RE(THF) with LH 2 in a 1:1 M ratio or salt metathesis reaction of LLi 2 (THF) x with anhydrous RECl 3 , then with NaOAr in THF. Complexes 1 – 4 were well characterized by elemental analyses and IR, as well as NMR spectroscopy in the case of complex 1 . The definitive molecular structures of complexes 1 – 4 were determined by single-crystal X-ray analysis. The catalytic behaviors of these complexes for rac -LA polymerization were investigated. It was found that complexes 1 – 4 can initiate efficiently this polymerization and gave hetero-rich PLA. Kinetics study demonstrated that rac -LA polymerization initiated by complexes 1 – 3 has a first order relationship between polymerization rate and monomer concentration. A comparative kinetics study in THF and CHCl 3 revealed that polymerization media have significant influence on the activity order of complexes 1 – 3 for rac -LA polymerization. The observed activity-increasing order of these complexes in THF is in agreement with the increasing order of their ionic radii, whereas it is in reverse order in CHCl 3 . A mechanism study demonstrated that the polymerization proceeded via a coordination-insertion mechanism, and the aryloxo group in these complexes acted as the initiating group.

Sillago sihama has high economic value and is one of the most attractive aquaculture species in China. Despite its economic importance, studies of its genome have barely been performed. In this study, we conducted a first genomic survey of S. sihama using next-generation sequencing (NGS). In total, 45.063 Gb of high-quality sequence data were obtained. For the 17-mer frequency distribution, the genome size was estimated to be 508.50 Mb. The sequence repeat ratio was calculated to be 21.25%, and the heterozygosity ratio was 0.92%. Reads were assembled into 1,009,363 contigs, with a N50 length of 1362 bp, and then into 814,219 scaffolds, with a N50 length of 2173 bp. The average Guanine and Cytosine (GC) content was 45.04%. Dinucleotide repeats (56.55%) were the dominant form of simple sequence repeats (SSR).

Ionic rare-earth metal complexes 1–4 bearing an imidazolium cation were synthesized, which, as single-component catalysts, showed good activity in catalyzing cyclic carbonate synthesis from epoxides and CO2. In the presence of 0.2 mol % catalyst, monosubstituted epoxides bearing different functional groups were converted into cyclic carbonates in 60–97% yields under atmospheric pressure. In addition, bulky/internal epoxides with low reactivity yielded cyclic carbonates in 40–95% yields. More importantly, the readily available samarium complex 2 was reused for six successive cycles without any significant loss in its catalytic activity. This is the first recyclable rare-earth metal-based catalyst in cyclic carbonate synthesis.

In 2 Si 2 O 7 is a known indium-based scintillator with fast ultraviolet photoluminescence. Unfortunately the emission only can be detected below 200 K. the poor thermal stability limits its application at room temperature. In this work, the luminescence improvement of In 2 Si 2 O 7 was realized by F − -ions doping in the lattices. The ceramic phosphors were via typical solid-state reaction method. The pure crystalline phase with thortveirite-type structure was confirmed by X-ray diffraction (XRD) Rietveld refinements. The photoluminescence (PL) emission and excitation spectra together with the luminescence thermal stability were tested. The fluorescence decay curves CIE emission Stokes shifts were measured. The ceramic samples could present blue luminescence with maximum wavelength at about 340 nm under the excitation of UV light or high energy X-ray irradiation. The pure sample only presents luminescence below 200 K, however, the F-doping can be greatly enhance the luminescence thermal stability. The F-doped In 2 Si 2 O 7 could present emission signals with fast decay lifetime of 850 ns at room temperature. The luminescence transitions from the In 3+ -O 2− charge transfer (CT) were discussed on the structure properties.

Pure and V 5+ -doped Bi 6 Mo 2 O 15 (3Bi 2 O 3 ·2MoO 3 ) photocatalysts were synthesized through electrospinning, followed by low-temperature heat treatment. The samples developed into nanoparticles with an average size of approximately 50 nm. The crystalline phases were verified via X-ray powder diffraction measurements (XRD). The surface properties of the photocatalysts were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The UV–vis spectra showed that V doping in Bi 6 Mo 2 O 15 shifted the optical absorption from the UV region to the visible-light wavelength region. The energy of the band gap of Bi 6 Mo 2 O 15 was reduced by V doping in the lattices. The photocatalytic activities of the pure and V-doped Bi 6 Mo 2 O 15 were tested through photodegradation of rhodamine B (RhB) dye solutions under visible light irradiation. Results showed that 20 mol% V-doped Bi 6 Mo 2 O 15 achieved efficient photocatalytic ability. RhB could be degraded by V-doped Bi 6 Mo 2 O 15 in 2 h. The photocatalytic activities and mechanisms were discussed according to the characteristics of the crystal structure and the results of EIS and XPS measurements.

Different aluminum complexes were synthesized by the reaction of aluminum alkyls with a hexadentate salen-type Schiff base. The reaction of N,N′-bis(3,5-di-tert-butylsalicylidene)-2,2′-(ethylenedioxy)dianiline (LH2) with one equiv. of AlMe3 in toluene at 100 °C proceeded by methane elimination to produce the intermediate methyl complex [AlMeL] (1), and then subsequent intramolecular methyl migration to give the aluminum complex [AlL′] (2) [L′ = (2-O-3,5-tBu2C6H2)CHNC6H4OCH2CH2OC6H4NCH(Me)(2′-O-3′,5′-tBu2C6H2)]. The reaction of the same ligand with AlEt3 under the same experimental conditions involved ethane elimination, ethylene elimination and intramolecular hydrogen migration, and led to the complex [AlL′′] (3) [L′′ = (2-O-3,5-tBu2C6H2)CHNC6H4OCH2CH2OC6H4NCH2(2′-O-3′,5′-tBu2C6H2)]. However, the interaction of two equivalents of AlMe3 and AlEt3 afforded the corresponding binuclear complexes [(AlMe2)2L] (4) and [(AlEt2)2L] (5), respectively, and no methyl or hydrogen migration was found. The solid-state structures of aluminum complexes 1–3 were determined by single-crystal X-ray diffraction. It was found that complexes 2–5 show a very effective catalytic activity for the cycloaddition of epoxides and CO2 in the presence of NBu4Br as a cocatalyst at atmospheric pressure.

Transition metal oxide In 2 Fe 2 CuO 7 nanoparticles were prepared by the sol-gel film coating and subsequent sintering method. The phase formation was investigated by X-ray polycrystalline diffraction (XRD) measurement. The structure refinement confirmed that the sample has a pure hexagonal phase with the space group of P 63/ mmc . The detailed surface properties were characterized. In 2 Fe 2 CuO 7 shows an efficient optical absorption in the region of visible wavelength and has a narrow band-gap of 1.91 eV. Particularly, In 2 Fe 2 CuO 7 presents the efficient photodegradation for methylene blue (MB) solutions under visible-light irradiation. The nanoparticles could be a potential photocatalyst for the photodegradation for organic pollution solutions.

A series of neutral lanthanide alkoxide complexes stabilized by a new salen-type Schiff-base ligand were synthesized, and their catalytic behaviors for the ring-opening polymerization of lactide were explored. Amine elimination reactions of N-methyl-N′,N″-bis(3,5-di-tert-butylsalicylidene)-2,2′-diaminodiethylamine (LH2) with Ln[N(SiMe3)2]3 (Ln = Sm, Nd, La) in a 1:1 M ratio in THF, followed by reactions with 1 equiv of alcohols (tBuOH, EtOH and CH3OCH2CH2OH), produced lanthanide alkoxide complexes LLn(OtBu)(THF) (Ln = Sm (1), Nd (2), La (3)), [LSm(μ-OEt)]2 (4) and [LSm(μ-OCH2CH2OCH3)]2 (5), respectively, whereas the same reaction with Yb[N(SiMe3)2]3 gave an unexpected homoleptic complex L2Yb2(μ-L) (6). X-ray structural determination showed that complexes 1–3 have a THF-solvated monomeric structure, whereas complexes 4–6 have an unsolvated dimeric structure. All lanthanide alkoxide complexes can efficiently initiate the ring-opening polymerization (ROP) of L-LA and rac-LA. The polymerization kinetics of L-LA initiated by complex 1 has been studied in detail and the first-order kinetic dependence on both l -lactide concentration and initiator concentration was found. Furthermore, all complexes showed moderate stereoselectivity for rac-LA polymerization to afford heterotactic-rich polylactides.

A series of lanthanide monoborohydride complexes stabilized by a bulky β-diketiminato ligand were synthesized, and their catalytic behaviors for the ring-opening polymerization of lactide were explored. Reaction of LnCl3 with two equivalents of NaL2-tBu (L2-tBu = {(2-tBuC6H4)NC(Me)}2CH−) afforded the bis(β-diketiminato) lanthanide monochlorides (L2-tBu)2LnCl (Ln = Y (1), Sm (2), Nd (3), La (4)), which can be used as starting materials to prepare bis(β-diketiminato) lanthanide derivatives. Treatment of the chlorides with NaBH4 produced the monoborohydride complexes (L2-tBu)2LnBH4 (Ln = Y (5), Sm (6), Nd (7), La (8)). The solid-state structures of lanthanide complexes 1–8 were determined by single-crystal X-ray diffraction. Complexes 5–8 were found efficient in initiating the ring-opening of l -lactide and rac-lactide to afford α,ω-telechelic polylactide diols.

International audience; Three heterometallic rare earth metal-zinc complexes were synthesized and structurally characterized. They catalyzed the cycloaddition of CO2 with epoxides at ambient temperature and pressure, which generated a wide range of cyclic carbonates in good yield (44-98%). This is the first rare earth metal-based homogenous catalysts, which are active and recyclable under ambient conditions. The synergistic effect of the two metal centers is evidenced by means of computational study.

Cationic zirconium complexes in situ generated from zirconium dibenzyl complexes bearing amine-bridged bis(phenolato) ligands have been developed to catalyze addition of C(sp2)–H and C(sp3)–H bonds of pyridine derivatives to alkenes. A series of zirconium complexes bearing different ligands have been synthesized, and their activities in catalyzing addition of C(sp3)–H bonds of pyridine derivatives to alkenes have been studied and compared. Both reaction activity and regioselectivity are influenced by electronic and steric properties of ligand backbones. In addition, a cationic zirconium complex has been isolated and structurally characterized to shed some light on reaction mechanism.