Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicabl...Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicable to aromatic, unsaturated and aliphatic aldehydes and to substituted o-phenylenediamines without significant differences.展开更多
An efficient BF3.OEt2-promoted benzylation of arenes and heteroarenes with various benzyl ether derivatives has been developed. This method provided alternative access to valuable diarylmethane in good yields under mi...An efficient BF3.OEt2-promoted benzylation of arenes and heteroarenes with various benzyl ether derivatives has been developed. This method provided alternative access to valuable diarylmethane in good yields under mild conditions via an easy work-up procedure.展开更多
“一带一路”背景下,结合世界上护理领域最权威的国际护理专业英语技能认证考试(Occupational English Test for Nursing,OET),从优化课程理念、序化课程结构和建构习得式教学活动3个方面探讨基于国际职业资格标准的高职护理英语课程改...“一带一路”背景下,结合世界上护理领域最权威的国际护理专业英语技能认证考试(Occupational English Test for Nursing,OET),从优化课程理念、序化课程结构和建构习得式教学活动3个方面探讨基于国际职业资格标准的高职护理英语课程改革策略。展开更多
A cubane-type molybdenum cluster compound Mo4S4(DTP)4[-SOP(OEt)2]2 A (DTP = diethyl dithiophosphate) was obtained from the reaction of cation [Mo3O2S2(H2O)9]4+ B with metal tin as well as HDTP. The crystal structure h...A cubane-type molybdenum cluster compound Mo4S4(DTP)4[-SOP(OEt)2]2 A (DTP = diethyl dithiophosphate) was obtained from the reaction of cation [Mo3O2S2(H2O)9]4+ B with metal tin as well as HDTP. The crystal structure has been determined by X-ray crystallography and the data for the title compound: Mo4S14P6O14C24H60, triclinic P , Mr = 1591.14, a = 12.5596(5), b = 14.3441(5), c = 18.0005(6) ? = 85.318(1), = 70.495(1), = 78.415(2)? V = 2994.2(2) ?, Z = 2, Dc = 1.765 g/cm3, (MoK? = 1.515 mm-1, F(000) = 1596, R = 0.0918 and wR = 0.1908 for 3546 reflections (I > 2(I)). X-ray analysis reveals that two weak CH贩稯 hydrogen bonds exist in the packing diagram with C贩稯 distance 3.22(5) ? The structure of A is similar to that of -Mo4S4(DTP)6 except that one sulfur of each bridging DTPs has been replaced by oxygen during the reaction, resulting in two bridging [SOP(OEt2)2] - ligands.展开更多
In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an inte...In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an internal donor(ID). The chemical compositions of the activated support and the prepared catalyst were examined in detail. During the dissolution of Mg(OEt) 2 support in ethanol medium with CO 2 bubbling, the structure of support changed to magnesium hydrocarbyl carbonate, (CH 3CH 2O) 2- x Mg(O (C O) OCH 2CH 3) x ( x = 1,2). The content of carbonated CO 2 in the activated support was dependent on the heat treatment in the solidification of support. In the preparation procedure of polymerization catalyst, the activated support was treated with TiCl 4 so that the structure of support was converted to MgCl 2 with the incorporation of ID. The polymerization behavior of the pre-pared catalyst was also studied in the presence of phenyltriethoxysilane as an external donor.展开更多
BF3·OEte （Boron trifluoride etherate）, an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann rearrangement in general, was now found to efficiently catalyze Beckm...BF3·OEte （Boron trifluoride etherate）, an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann rearrangement in general, was now found to efficiently catalyze Beckmann rearrangement of ketoximes into their corresponding amides （up to 99% yield） in anhydrous acetonitrile under reflux temperature.展开更多
During the investigation of trinuclear molybdenum cluster, it has been found that the bidentate ligand [S2P（OEt）2]- may be used either as a terminal chelating group or as a bridging group of two Mo atoms, so that it...During the investigation of trinuclear molybdenum cluster, it has been found that the bidentate ligand [S2P（OEt）2]- may be used either as a terminal chelating group or as a bridging group of two Mo atoms, so that it may have the advantage of forming cluster compounds. We thus obtained previously a cubane-like tetranuclear cluster {Mo4（μ3-S）3（μ3-O）-[S2P（OEt）2]6} based on [S2P（OEt）2]- ligands, and now bv changing the reaction展开更多
Ⅰ. INTRODUCTION With more and more clusters being synthesized there have been found some clusters in which the metal atom has only weak interaction with its one or more ligands, or the ligand is even lost, leaving an...Ⅰ. INTRODUCTION With more and more clusters being synthesized there have been found some clusters in which the metal atom has only weak interaction with its one or more ligands, or the ligand is even lost, leaving an 'empty' site about the metal atomic coordination展开更多
Cyclic voltammetric studies of clusters(C_6H_5-C_2C_6 H_4-R-p)Co_2(CO)_(6-n) L_n[n=0,2; L=PPh_3,P(OEt)_3] and(RCH_2C)_2Co_2(CO_4)(PPh_3)_2 on Pt electrode are described. The primary reduction(0/-1)and oxidation (+1/0)...Cyclic voltammetric studies of clusters(C_6H_5-C_2C_6 H_4-R-p)Co_2(CO)_(6-n) L_n[n=0,2; L=PPh_3,P(OEt)_3] and(RCH_2C)_2Co_2(CO_4)(PPh_3)_2 on Pt electrode are described. The primary reduction(0/-1)and oxidation (+1/0) steps are considered as a mono-electron process for all clusters. For the clusters (C_6H_5C_2C_6H_4-R-P)Co_2(CO)_6, a good linear relation between reduction poten- tial EF_p^(red) and Hammett constant σp of R in the clusters is found. For the clusters(RC_2R′)Co_2(CO)_4L_2, their radical anions are extremely unstable at room temperature and fragment into a series of mono- nuclear species, one of which is(RC-3R′)Co(CO)_2PPh_3. The reaction of radical anions of (RC_2R’)- Co_2(CO)_(6-n) (PPh_3)_n(n=0,2) with PPh_3 also produces mononuclear species (RC_2R’)Co(CO)_2PPh_3 which has been detected by means of cyclic voltammetry and ESR. The influence of R on redox pro- perties of clusters is discussed.展开更多
文摘Differently substituted benzimidazoles have been synthesized in very good yields in solvent-free conditions from o-phenylenediamine and aldehydes in the presence of BF3·OEt2 as a catalyst. The method is applicable to aromatic, unsaturated and aliphatic aldehydes and to substituted o-phenylenediamines without significant differences.
文摘An efficient BF3.OEt2-promoted benzylation of arenes and heteroarenes with various benzyl ether derivatives has been developed. This method provided alternative access to valuable diarylmethane in good yields under mild conditions via an easy work-up procedure.
基金This work was financially supported by the NNSF of China (No. 29733090 and No. 20173063) Key Project in KIP of CAS (KJCX2-H3) and the NNSF of Fujian Province (E0020001)
文摘A cubane-type molybdenum cluster compound Mo4S4(DTP)4[-SOP(OEt)2]2 A (DTP = diethyl dithiophosphate) was obtained from the reaction of cation [Mo3O2S2(H2O)9]4+ B with metal tin as well as HDTP. The crystal structure has been determined by X-ray crystallography and the data for the title compound: Mo4S14P6O14C24H60, triclinic P , Mr = 1591.14, a = 12.5596(5), b = 14.3441(5), c = 18.0005(6) ? = 85.318(1), = 70.495(1), = 78.415(2)? V = 2994.2(2) ?, Z = 2, Dc = 1.765 g/cm3, (MoK? = 1.515 mm-1, F(000) = 1596, R = 0.0918 and wR = 0.1908 for 3546 reflections (I > 2(I)). X-ray analysis reveals that two weak CH贩稯 hydrogen bonds exist in the packing diagram with C贩稯 distance 3.22(5) ? The structure of A is similar to that of -Mo4S4(DTP)6 except that one sulfur of each bridging DTPs has been replaced by oxygen during the reaction, resulting in two bridging [SOP(OEt2)2] - ligands.
文摘In the preparation of catalyst for propylene polymerization, the Mg(OEt) 2 support was activated with ethanol/CO 2 system followed by solidification, and treated with TiCl 4 in the presence of ethylbenzoate as an internal donor(ID). The chemical compositions of the activated support and the prepared catalyst were examined in detail. During the dissolution of Mg(OEt) 2 support in ethanol medium with CO 2 bubbling, the structure of support changed to magnesium hydrocarbyl carbonate, (CH 3CH 2O) 2- x Mg(O (C O) OCH 2CH 3) x ( x = 1,2). The content of carbonated CO 2 in the activated support was dependent on the heat treatment in the solidification of support. In the preparation procedure of polymerization catalyst, the activated support was treated with TiCl 4 so that the structure of support was converted to MgCl 2 with the incorporation of ID. The polymerization behavior of the pre-pared catalyst was also studied in the presence of phenyltriethoxysilane as an external donor.
基金Project supported by the National Natural Science Foundation of China （No. 20602011）, New Century Excellent Talents in University, the Ministry of Education, China （No. NCET-07-0283）, and ‘111＇ Project （No. B07023）.
文摘BF3·OEte （Boron trifluoride etherate）, an inexpensive and commercially easily available Lewis acid stoichiometrically employed for Beckamann rearrangement in general, was now found to efficiently catalyze Beckmann rearrangement of ketoximes into their corresponding amides （up to 99% yield） in anhydrous acetonitrile under reflux temperature.
文摘During the investigation of trinuclear molybdenum cluster, it has been found that the bidentate ligand [S2P（OEt）2]- may be used either as a terminal chelating group or as a bridging group of two Mo atoms, so that it may have the advantage of forming cluster compounds. We thus obtained previously a cubane-like tetranuclear cluster {Mo4（μ3-S）3（μ3-O）-[S2P（OEt）2]6} based on [S2P（OEt）2]- ligands, and now bv changing the reaction
文摘Ⅰ. INTRODUCTION With more and more clusters being synthesized there have been found some clusters in which the metal atom has only weak interaction with its one or more ligands, or the ligand is even lost, leaving an 'empty' site about the metal atomic coordination
基金This project was supported by the National Natural Science Foundation of China as an item of major project.
文摘Cyclic voltammetric studies of clusters(C_6H_5-C_2C_6 H_4-R-p)Co_2(CO)_(6-n) L_n[n=0,2; L=PPh_3,P(OEt)_3] and(RCH_2C)_2Co_2(CO_4)(PPh_3)_2 on Pt electrode are described. The primary reduction(0/-1)and oxidation (+1/0) steps are considered as a mono-electron process for all clusters. For the clusters (C_6H_5C_2C_6H_4-R-P)Co_2(CO)_6, a good linear relation between reduction poten- tial EF_p^(red) and Hammett constant σp of R in the clusters is found. For the clusters(RC_2R′)Co_2(CO)_4L_2, their radical anions are extremely unstable at room temperature and fragment into a series of mono- nuclear species, one of which is(RC-3R′)Co(CO)_2PPh_3. The reaction of radical anions of (RC_2R’)- Co_2(CO)_(6-n) (PPh_3)_n(n=0,2) with PPh_3 also produces mononuclear species (RC_2R’)Co(CO)_2PPh_3 which has been detected by means of cyclic voltammetry and ESR. The influence of R on redox pro- perties of clusters is discussed.
