Hongting Sheng

Name: 盛鸿婷; HongTing Sheng

Organization: Anhui University , China

Department: School of Chemistry and Chemical Engineering & Key Laboratory of Environment-friendly Polymer Materials of Anhui Province

Title: Associate Professor(PhD)

TOPICS

Inorganic Chemistry

Metal Clusters

Chemicals
References

Heterobimetallic dinuclear lanthanide alkoxide complexes as acid–base bifunctional catalysts for synthesis of carbamates under solvent-free conditions

Co-reporter:Ruijie Zeng, Linquan Bao, Hongting Sheng, Lili Sun, Man Chen, Yan Feng and Manzhou Zhu

RSC Advances 2016 vol. 6(Issue 82) pp:78576-78584

Publication Date(Web):09 Aug 2016

DOI:10.1039/C6RA15160D

Heterobimetallic dinuclear lanthanide alkoxide complexes Ln2Na8(OCH2CH2NMe2)12(OH)2 [Ln: I (Nd), II (Sm), III (Yb) and IV (Y)] were used as efficient acid–base bifunctional catalysts for the synthesis of carbamates from dialkyl carbonates and amines as well as the N-Boc protection of amines. The cooperative catalysts showed high catalytic activity and a wide scope of substrates with good to excellent yields under solvent-free conditions. The systems have shown higher catalytic activities due to the noteworthy synergistic interactions of Lewis acid center–Brønsted basic center. The comparison of catalytic efficiency between mono- and dinuclear heterobimetallic lanthanide alkoxide analogues was also investigated.

Heteroatom Effects on the Optical and Electrochemical Properties of Ag25(SR)18 and Its Dopants

Co-reporter:Xi Kang;Shuang Chen;Shan Jin;Yongbo Song;Yajie Xu; Haizhu Yu; Hongting Sheng; Manzhou Zhu

ChemElectroChem 2016 Volume 3( Issue 8) pp:1261-1265

Publication Date(Web):

DOI:10.1002/celc.201600038

Abstract

The structure–property correlations of silver nanoclusters (NCs) have rarely been studied, owing to the lack of appropriate materials and the instability of silver NCs. Herein, we show that substituting the central atom of the Ag₂₅(SR)₁₈ NC with another metal atom (i.e. Pd, Pt, or Au) can influence the optical and electrochemical properties. The significant blueshift in optical absorption spectra (compared to Ag₂₅) illustrates the unique electronic perturbation caused by the incorporated heteroatom. In addition, voltammetric measurements were performed to explore the electrochemical properties of Ag NCs for the first time. The O2−O1 potential spacings for different NCs follow the sequence of Pd₁Ag₂₄< Ag₂₅< Pt₁Ag₂₄< Au₁Ag₂₄, and this sequence explains the instability of Ag₂₅ compared to Au₁Ag₂₄. Meanwhile, the HOMO–LUMO gaps calculated from differential pulse voltammetry measurements are consistent with those derived from the optical absorption spectra. This study provides further understanding of the structure–property correlations of Ag NCs.

A metal exchange method for thiolate-protected tri-metal M1AgxAu24−x(SR)180 (M = Cd/Hg) nanoclusters

Co-reporter:Sha Yang, Shuxin Wang, Shan Jin, Shuang Chen, Hongting Sheng and Manzhou Zhu

Nanoscale 2015 vol. 7(Issue 22) pp:10005-10007

Publication Date(Web):05 May 2015

DOI:10.1039/C5NR01965F

We herein reported the first synthesis of tri-metallic M1AgxAu24−x(SR)180 (M = Cd/Hg) nanoclusters by a two-step metal exchange method. Optical spectra suggested that the second and third foreign metals could largely change the electronic structure of homogold Au25(SR)18− nanoclusters. This work also provides a novel way to find the doping site of some special metals (such as Cd), which can be done using silver as the isotope of gold.

Monodispersed AuPd nanoalloy: composition control synthesis and catalytic properties in the oxidative dehydrogenative coupling of aniline

Co-reporter:Fangyu Fu;Sen He;Sha Yang;Chen Wang;Xun Zhang;Peng Li

Science China Chemistry 2015 Volume 58( Issue 10) pp:1532-1536

Publication Date(Web):2015 October

DOI:10.1007/s11426-015-5358-1

A series of AuPd@C nanoalloy catalysts with tunable compositions were successfully prepared by a co-reduction method. The use of borane-tert-butylamine complex as reductant and oleylamine as both solvent and reductant was very effective for the preparation of the monodispersed nanoalloy. We evaluated the catalytic activity of these AuPd@C nanoalloys for oxidative dehydrogenative coupling of aniline, which showed better catalytic activity than equal amounts of sole Au@C or Pd@C catalyst. The Au1Pd3@C catalyst exhibited the best performance, indicating that the conversion and selectivity were improved along with the increase of Pd composition. However if the Pd composition was too high in the AuPd alloy, Au1Pd7@C achieved only 81% conversion in this reaction.

An efficient and green approach to synthesizing enamines by intermolecular hydroamination of activated alkynes

Co-reporter:Ruijie Zeng;Bo Rao;Yan Feng

Chemical Research in Chinese Universities 2015 Volume 31( Issue 2) pp:212-217

Publication Date(Web):2015/04/01

DOI:10.1007/s40242-015-4388-8

Pd–Ni Alloy Nanoparticles as Effective Catalysts for Miyaura–Heck Coupling Reactions

Co-reporter:Li Feng

The Journal of Physical Chemistry C 2015 Volume 119(Issue 21) pp:11511-11515

Publication Date(Web):March 30, 2015

DOI:10.1021/jp510988m

In this work, Pd–Ni alloy nanoparticles (NPs) were produced by a facile and efficient one-pot synthetic strategy in the presence of oleylamine (OAm) and triphenylphosphine (TPP). Transmission electron microscopy (TEM), energy-dispersive spectrometry (EDS) mapping, inductively coupled plasma atomic emission spectroscopy (ICP-AES), and X-ray diffraction (XRD) were used to investigate the structure of Pd–Ni alloy NPs, which demonstrated that the as-prepared alloy NPs possessed uniform sizes and tunable compositions. Importantly, we found that TPP could affect the morphology of the Pd–Ni alloy. When TPP was absent from the reaction, the morphology of the Pd–Ni alloy was not uniform. In addition, the as-prepared Pd–Ni alloy NPs showed conspicuous composition-dependent catalytic activities for the Miyaura–Heck reaction. In the series of the Pd–Ni alloy NPs, Pd1Ni1 has an excellent effect for the Miyaura–Heck reactions. Furthermore, the Pd–Ni alloy NPs were also effective for different substrates in the Miyaura–Heck reactions. Compared to pure palladium, the Pd–Ni alloy NPs as the catalysts show better catalytic activity, selectivity, and stability.

Heterobimetallic Dinuclear Lanthanide Alkoxide Complexes as Acid–Base Difunctional Catalysts for Transesterification

Co-reporter:Ruijie Zeng, Hongting Sheng, Yongcang Zhang, Yan Feng, Zhi Chen, Junfeng Wang, Man Chen, Manzhou Zhu, and Qingxiang Guo

The Journal of Organic Chemistry 2014 Volume 79(Issue 19) pp:9246-9252

Publication Date(Web):September 10, 2014

DOI:10.1021/jo5016536

A practical lanthanide(III)-catalyzed transesterification of carboxylic esters, weakly reactive carbonates, and much less-reactive ethyl silicate with primary and secondary alcohols was developed. Heterobimetallic dinuclear lanthanide alkoxide complexes [Ln2Na8{(OCH2CH2NMe2)}12(OH)2] (Ln = Nd (I), Sm (II), and Yb (III)) were used as highly active catalysts for this reaction. The mild reaction conditions enabled the transesterification of various substrates to proceed in good to high yield. Efficient activation of transesterification may be endowed by the above complexes as cooperative acid–base difunctional catalysts, which is proposed to be responsible for the higher reactivity in comparison with simple acid/base catalysts.

Remarkable effect of alkali metal on polymerization of cyclic esters catalyzed by samarium–alkali metal multinuclear alkoxide clusters

Co-reporter:Hongting Sheng, Jianhua Shi, Yan Feng, Hui Wang, Yonghua Jiao, Hanjing Sheng, Yong Zhang and Qi Shen

Dalton Transactions 2012 vol. 41(Issue 30) pp:9232-9240

Publication Date(Web):21 May 2012

DOI:10.1039/C2DT30677H

The remarkable effect of alkali metal on catalytic reactivity of samarium–alkali metal multinuclear alkoxide clusters is systematically studied. Three samarium–alkali metal multinuclear alkoxide clusters are synthesized in high yield by the reaction of anhydrous SmCl3 with different molar ratios of alkali metal alkoxide and MOH (M = Na or K) in tetrahydrofuran (THF). These clusters were fully characterized by elemental analysis, IR, 1H NMR and single-crystal structural analysis. These clusters exhibited good catalytic activity for the ring-opening polymerization of ε-caprolactone (ε-CL), L-lactide (L-LA) and trimethylene carbonate (TMC). It is interesting to note that the catalytic activity is much influenced by the alkali metals of the clusters. For the polymerization of these cyclic esters, the catalytic activities all increase with the increase of the molar ratio of alkali metal to samarium metal.

Synthesis and Crystal Structure of Novel Biheterometal and Triheterometal Alkoxide Clusters Highly Active Catalysts for the Polymerization of -Caprolactone

Co-reporter:Hongting Sheng;Yan Feng;Yong Zhang;Qi Shen

European Journal of Inorganic Chemistry 2010 Volume 2010( Issue 35) pp:5579-5586

Publication Date(Web):

DOI:10.1002/ejic.201000831

Abstract

The effect of the alkali metal on the synthesis, crystal structure, and catalytic reactivity of lanthanide–alkali metal alkoxide clusters is reported. Anhydrous LnCl₃ reacts with 6.5 equiv. of KOCH₂CH₂N(CH₃)₂ and 1.5 equiv. of KOH in tetrahydrofuran (THF) to give the corresponding lanthanide–potassium biheterometal alkoxide clusters [Ln₄K₂₀(OCH₂CH₂NMe₂)₂₆(OH)₆] [Ln = Nd (1), Pr (2), Yb (3)] in high yield. Anhydrous YbCl₃ reacts with KOCH₂CH₂N(CH₃)₂ and NaOH with different molar ratios of 1:9:3 and 1:9:4 to afford the lanthanide–potassium–sodium triheterometal alkoxide clusters [Yb₂K₁₀Na₆(OCH₂CH₂NMe₂)₁₈(OH)₄] (4) and [Yb₂K₈Na₈(OCH₂CH₂NMe₂)₁₈(OH)₄] (5), respectively. These clusters were fully characterized by elemental analysis, IR, ¹H NMR, and single-crystal structural analysis. The heterometal alkoxide clusters 1–5 exhibited good catalytic activity for the ring-opening polymerization of ϵ-caprolactone (ϵ-CL). It is interesting to note that the catalytic activity of these heterometal alkoxide clusters increases with the increase of the molar ratio of alkali metal to lanthanide metal. For the same molar ratio of alkali metal to lanthanide metal, however, the catalytic activity of the heterometal clusters is highly dependent on the type and molar ratio of the alkali metal centers. The higher the molar ratio of potassium to sodium, the higher the catalytic activity.