The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0....The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.展开更多
The cluster compound[Mo_4S_4(μ-O_2CC_5H_5)_2(dtp)_4](dtp=S_2P(OEt)_2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo_4S_4(μ-dtp)_2(dtp)_4]in the mixed solvent of acetone,ethan...The cluster compound[Mo_4S_4(μ-O_2CC_5H_5)_2(dtp)_4](dtp=S_2P(OEt)_2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo_4S_4(μ-dtp)_2(dtp)_4]in the mixed solvent of acetone,ethanol and water in the presence of C_6H_5CO_2Na.It is monoclinic and crystallizes in space group C2/c, Mr=1495.09,a=12.175(5),b=22.01(1),c=20.875(9),β=99.04(4)°;V=5575(5);Z=4; Dc=1.78g/cm^3.Final R factor is 0.066.The result reveals that the[Mo_4S_4]cluster core and t-(dtp)^(-1)ligands are retained and only μ-bridged(dtp)^(-1)ligands are substituted by(C_6H_5CO_2)^(-1)in the substitution reaction,thus producing the new title cluster compound,the structure of which contains two species of bidentate ligand.展开更多
The crystal of the title compound with formula C36H44Cl2F3Mo2NO8S2 (Mr = 10002.62) crystallized in monoclinic, space group P21/n, with a = 9.6184(1), b = 22.3476(2), c = 20.7758(2) ?, ( = 90.172(1)(, V = 4465.70(7) ?3...The crystal of the title compound with formula C36H44Cl2F3Mo2NO8S2 (Mr = 10002.62) crystallized in monoclinic, space group P21/n, with a = 9.6184(1), b = 22.3476(2), c = 20.7758(2) ?, ( = 90.172(1)(, V = 4465.70(7) ?3, Z = 4, Dc = 1.491 g/cm3, F(000) = 2032, ( = 0.833 mm-1, Final R = 0.0665 and wR = 0.1650 for 5044 reflections with I >2.0( (I). The crystal structure revealed that the Mo2S2 core is planar, and the trifluoroacetic group acts as a bidentate bridging ligand and coordinates to two Mo atoms forming a five-membered ring plane, in which the Mo-Mo bond distance is 2.9222(9) ? and the O-C-O angle is 131.8(7)展开更多
The title compound was prepared by the reaction of Mo_3S_4(dtp)_4(H_2O)[ctp=S_2P(OEt)_2] with NaOAc·3H_2O and C_4H_8NCS_2NH_4.Crystallographic data:[Mo_3(μ_3-S)(μ-S)_2(μ-OAc)- (S_2CNC_4H_8)_3(O)_2]·0.5CH_...The title compound was prepared by the reaction of Mo_3S_4(dtp)_4(H_2O)[ctp=S_2P(OEt)_2] with NaOAc·3H_2O and C_4H_8NCS_2NH_4.Crystallographic data:[Mo_3(μ_3-S)(μ-S)_2(μ-OAc)- (S_2CNC_4H_8)_3(O)_2]·0.5CH_2CI_2·2H_2O,Mr=980.18,triclinic,space group P(?),α=12.360(3),b=16.653(6), c=9.206(2)A,α=101.97(2),β=108.32(2),γ=86.14(3)°.V=1759.6(9)A^3,Z=2,Dc=1.85 g/cm^3, F(000)=962,μ(Mo K_α)=16.53 cm^(-1).Final R=0.044 for 4301 reflections with I≥3σ(I).This compound may be regarded as a mixed-valent trinuclear molybdenum cluster{Mo_2(V)Mo(Ⅳ)(μ_3-S)(μ-S)_2- (μ-OAc)(S_2CNC_4H_8)_3(O)_2}.The Mo-Mo distances are 2.783(1),2.833(1)and 3.374(2)A in the Mo_3 non-equilateral triangle and there exist only two Mo-Mo bonds.The cluster was obtained by oxi- dation and ligand substitution of{Mo_3(μ_3-S)(μ-S)_3[μ-S_2P(OEt_2)][S_2P(OEt)_2]_3(H_2O)}.展开更多
A novel mixed-trib ridged dimolybdenum(Ⅰ) compound [Bu4N][Mo2(n-SPh)2(u-Cl)(CO)6] (1) has been synthesized from the reaction of Mo2 (CO)8 (SPh)2 with ButNCl.Compound 1 was characterized by IR,UV-Vis and 1H,13C,95Mo N...A novel mixed-trib ridged dimolybdenum(Ⅰ) compound [Bu4N][Mo2(n-SPh)2(u-Cl)(CO)6] (1) has been synthesized from the reaction of Mo2 (CO)8 (SPh)2 with ButNCl.Compound 1 was characterized by IR,UV-Vis and 1H,13C,95Mo NMR spectroscopic analyses.The electrochemical behavior was measured by cyclic voltammetry,indicating a quasi-reversible two-electron transfer in one step.The crystal structure determined by X-ray crystallography shows that 1 contains a [Mo2(u-S)2(u-Cl)]- core with a planar Mo2S2 unit and a Cl bridge.The Mo-Mo distance is 0.28709(7) nm,and the Mo-Cl-Mo angle is 66.44(4).A newface-sharing bioctahedral structure is discussed.展开更多
In this Letter, a single-frequency fiber laser using a molybdenum disulfide (MoS2) thin film as a saturable absorber is demonstrated. We use a short length of highly Yb-doped fiber as the gain medium and a fiber fer...In this Letter, a single-frequency fiber laser using a molybdenum disulfide (MoS2) thin film as a saturable absorber is demonstrated. We use a short length of highly Yb-doped fiber as the gain medium and a fiber ferrule with MoS2 film adhered to it by index matching gel (IMG) that acts as the saturable absorber. The saturable absorber can be used to discriminate and select the single longitudinal modes. The maximum output power of the single-frequency fiber laser is 15,3 mW at a pump power of 130 mW and the slope efficiency is 15.3%. The optical signal-to-noise ratio and the laser linewidths are -60 dB and 5.89 kHz, respectively.展开更多
基金supported by the National Natural Science Foundation of China(21173100 and 21320102001)~~
文摘The catalytic epoxidation of olefin was investigated on two copper complex-modified molybdenum oxides with a 3D supramolecular structure, [Cu(bipy)]4[Mo15O47].2H2O (1) and [Cu1(bix)][(Cu1bix) (δ-MoVl8O26)0.5] (2) (bipy = 4,4'-bipyridine, bix = 1,4-bis(imidazole-1-ylmethyl)benzene). Both compounds were catalytically active and stable for the epoxidation of cyclooctene, 1-octene, and styrene with tert-butyl hydroperoxide (t-BuOOH) as oxidant. The excellent catalytic performance was attributed to the presence of stable coordination bonds between the molybdenum oxide and copper complex, which resulted in the formation of easily accessible Mo species with high electropositivity. In addition, the copper complex also acted as an active site for the activation of t-BuOOH, thus im- proving these copper complex-modified polyoxometalates.
文摘The cluster compound[Mo_4S_4(μ-O_2CC_5H_5)_2(dtp)_4](dtp=S_2P(OEt)_2)was obtained by the ligand substitution reaction of tetranuclear molybdenum cluster [Mo_4S_4(μ-dtp)_2(dtp)_4]in the mixed solvent of acetone,ethanol and water in the presence of C_6H_5CO_2Na.It is monoclinic and crystallizes in space group C2/c, Mr=1495.09,a=12.175(5),b=22.01(1),c=20.875(9),β=99.04(4)°;V=5575(5);Z=4; Dc=1.78g/cm^3.Final R factor is 0.066.The result reveals that the[Mo_4S_4]cluster core and t-(dtp)^(-1)ligands are retained and only μ-bridged(dtp)^(-1)ligands are substituted by(C_6H_5CO_2)^(-1)in the substitution reaction,thus producing the new title cluster compound,the structure of which contains two species of bidentate ligand.
文摘The crystal of the title compound with formula C36H44Cl2F3Mo2NO8S2 (Mr = 10002.62) crystallized in monoclinic, space group P21/n, with a = 9.6184(1), b = 22.3476(2), c = 20.7758(2) ?, ( = 90.172(1)(, V = 4465.70(7) ?3, Z = 4, Dc = 1.491 g/cm3, F(000) = 2032, ( = 0.833 mm-1, Final R = 0.0665 and wR = 0.1650 for 5044 reflections with I >2.0( (I). The crystal structure revealed that the Mo2S2 core is planar, and the trifluoroacetic group acts as a bidentate bridging ligand and coordinates to two Mo atoms forming a five-membered ring plane, in which the Mo-Mo bond distance is 2.9222(9) ? and the O-C-O angle is 131.8(7)
基金Work supported by the National Natural Science Foundation of China.
文摘The title compound was prepared by the reaction of Mo_3S_4(dtp)_4(H_2O)[ctp=S_2P(OEt)_2] with NaOAc·3H_2O and C_4H_8NCS_2NH_4.Crystallographic data:[Mo_3(μ_3-S)(μ-S)_2(μ-OAc)- (S_2CNC_4H_8)_3(O)_2]·0.5CH_2CI_2·2H_2O,Mr=980.18,triclinic,space group P(?),α=12.360(3),b=16.653(6), c=9.206(2)A,α=101.97(2),β=108.32(2),γ=86.14(3)°.V=1759.6(9)A^3,Z=2,Dc=1.85 g/cm^3, F(000)=962,μ(Mo K_α)=16.53 cm^(-1).Final R=0.044 for 4301 reflections with I≥3σ(I).This compound may be regarded as a mixed-valent trinuclear molybdenum cluster{Mo_2(V)Mo(Ⅳ)(μ_3-S)(μ-S)_2- (μ-OAc)(S_2CNC_4H_8)_3(O)_2}.The Mo-Mo distances are 2.783(1),2.833(1)and 3.374(2)A in the Mo_3 non-equilateral triangle and there exist only two Mo-Mo bonds.The cluster was obtained by oxi- dation and ligand substitution of{Mo_3(μ_3-S)(μ-S)_3[μ-S_2P(OEt_2)][S_2P(OEt)_2]_3(H_2O)}.
基金Project supported by the National Natural Science Foundation of China (No. 29733090-3)State Key Laboratory of Stractural Chemistry (No. 980008)
文摘A novel mixed-trib ridged dimolybdenum(Ⅰ) compound [Bu4N][Mo2(n-SPh)2(u-Cl)(CO)6] (1) has been synthesized from the reaction of Mo2 (CO)8 (SPh)2 with ButNCl.Compound 1 was characterized by IR,UV-Vis and 1H,13C,95Mo NMR spectroscopic analyses.The electrochemical behavior was measured by cyclic voltammetry,indicating a quasi-reversible two-electron transfer in one step.The crystal structure determined by X-ray crystallography shows that 1 contains a [Mo2(u-S)2(u-Cl)]- core with a planar Mo2S2 unit and a Cl bridge.The Mo-Mo distance is 0.28709(7) nm,and the Mo-Cl-Mo angle is 66.44(4).A newface-sharing bioctahedral structure is discussed.
基金supported by the National Natural Science Foundation of China(No.61475125)the Natural Science Foundation of Shaanxi Province,China(No.2016JM6083)the Science Foundation of Northwest University(No.15NW07)
文摘In this Letter, a single-frequency fiber laser using a molybdenum disulfide (MoS2) thin film as a saturable absorber is demonstrated. We use a short length of highly Yb-doped fiber as the gain medium and a fiber ferrule with MoS2 film adhered to it by index matching gel (IMG) that acts as the saturable absorber. The saturable absorber can be used to discriminate and select the single longitudinal modes. The maximum output power of the single-frequency fiber laser is 15,3 mW at a pump power of 130 mW and the slope efficiency is 15.3%. The optical signal-to-noise ratio and the laser linewidths are -60 dB and 5.89 kHz, respectively.